A question / statement that keeps coming up is that most people would not really be comparing using a 70-200 2.8 vs a 600mm for wildlife work. However, I get the question all the time, but it's more like a chain of thought where someone has long glass but it's on the slow side, like a 600 6.3 of coms flavor. The light gets dim or the background is too busy and they start thinking that maybe they should opt for the faster 200mm 2.8 or 300mm 2.8 instead of the slower 600mm 6.3 since the 2.8 is so much faster. It's not so much that people are trying to use a 200mm 2.8 for general wildlife work instead of the 600mm; it's that they have both optics and the low light or busy backgrounds make them start to think about that F/2.8 sitting in the bag.
What people seem to forget is what the F stands for in F number - focal length. The depth of field doesn't care about F-number per se; at 200mm f/2.8 you have roughly a 71mm aperture, but 600mm at f/6.3 is above 95mm, while 14mm f/2.8 is a mere 5mm aperture opening! Acceptable depth of field at a given subject distance increases with the physical aperture opening, if you simplify a standard DOF formula it's quite obvious. My shorthand is to actually look at the front element on a telephoto - the bigger it is, the shallower I can get DOF at a given subject distance.
@@jec6613 Wikipedia says that approximately DOF = (2*u^2*N*c)/f^2 , where f=focal-length, N=f-number, u=distance, and c=circle-of-confusion. So focal length (or distance changes) have a squared effect on DOF, but f-number (f-stop) only linear. So going from a 200mm to 400mm lens at the same aperture will give 1/4 the DOF, but you would need to drop your f-number *4* stops (ea stop is a factor of sqrt(2)) to achieve the same change with f-stop alone.
Hi, excellent video. AF is also affected in a complicated way, for example having 5 times more light will help a lot, but having a bigger subject too. Could you run a comparison? thanks !!!
@@jaimeduncan6167 AF is tricky than that. Although the system is getting more light, the target is much smaller and tougher to lock onto. I think it's more of a wash than people think. If I can devise a way to test it, I may do just that.
Gotta remember the next time I'm out photographing grizzlies, use the 70-200 and move 3 times closer..............no, wait, keep using the 400 or 800 6.3. Excellent Steve, thanks !!!
But then again, considering you'd have to open up a stop or so on the dark brown fur, wouldn't it be better to move closer with the 70 to 200 f2/.8? (Peace out, I'm just joking).
Got it right Steve because as you and others have pointed out in the past, and my own subjective observations to some extent, the longe lens compression wins even with considerably narrower apertures. Not having to crop, or nearly as much, is also a plus.
At 1:48 I got the answer correct. I took 600/200, we know that's 3.0. So then I multiplied 2.8 x 3.0 and got 8.4. The bokeh when cropped in 3x on that 2.8 will be more like 8.4, so I knew the lens with the lesser bokeh was the 70-200. Didn't know about the comparative ISO bit. Amazing video, loved it!
@@Mark-m6j8g Absolutely not. Background separation is about subject distance and the distance between the subject and the background more than anything else.
Hi Steve, I knew a lot of what you taught in this video. But I enjoyed watching it and the way you explained everything. TH-cam needs more no nonsense photography educators like you who know how to make beautiful images and also the technical aspects of the craft. I just subscribed to your channel.
@@julieng1312 I think Steve you’ve created a bit of confusion here by pushing a 70-200 f2.8 into what it’s not designed for. This video will be the most commented on & the most confusing to lots of people. @julieng1312, unfortunately an f2.8 will remain a reining king, while your & my 500mm f5.6 PF is a beauty but no match to 400mm f2.5 TC -Nikon engineers & all photographers know that
Pay them no mind. They would enjoy spending your money, probably more than they enjoyed spending their own. "Misery loves company", especially when the bills come in.
The 200mm focal length at f/2.8 has an aperture of 71.4mm, while the 600mm at f/6.3 has an aperture of 95.2mm. so as expected the larger aperture has the shallower depth of field. Our host says @2:42 "Focal length as much on your on your depth of field as aperture, and that is the critical thing to remember." No, the critical thing to remember is that aperture is in millimeters. For the 600mm lens to get the same aperture as the 200mm at f/2.8 we would stop it down to f/8.4, and that will produce the same depth of field in this kind of test, that is tests of the same scene and camera position and we will crop and enlarge to the same field of view at the same display size.
Thank you for focusing your attention to the physical size of the apertures - the depth of field calculations are based on this - not the calculated aperture. (pun intended)
I love that lens. Even though I have a 600 TC I tend to favor the 800 PF. If I know I’m gonna be in that focal range. It’s just so much lighter and easier to handle.
@@MrDaveB123 Are you referring to the f2.8 lens is not useful for environmental shots? You’ve got it wrong, the fast f2.8 lens allows the sensor to focus more accurately. It closes to f11 (or whatever you set it up) millisecond before actually clicking the short so that you get your composed hyperfocal shot. This lens will be far superior than an f4 or f5.6 lens for that reason & of course if you need subject isolation in an environmental shot you’ve got beautiful bokeh to play with -not all environmental shots have to have everything in pin sharp focus like your phone camera. Hence the price you pay. All photographers & lens manufacturers know this…I thought
My example... I bought the (Z) 100-400 when it first came out, and it has been an amazing tool, illustrating your points exactly, even creating convincing "macro" shots. (My 70-200 2.8 is a great lens, but I use it less often, because of that.) We are all so lucky to have these tools today! :)
The low-light situation as how I would apply it is to take photos of amphibians / insects at night time at close ranges. I would never shoot with the 200mm at the same distance at a 600mm but this was a good review / comparison none the less. Thank you for this.
Good luck in low light with your big lenses I had the joy of viewing feeding lions at dusk close to our vehicle the 2.8 was invaluable Predators come out to play as the sun goes down
Something very important to consider when buying is difficulty acquiring your subject. Try shooting a bif with the 600 f4. It’s extremely hard to find the bird in the viewfinder. It’s even hard finding them in a tree most of the time. Also the minimum focusing distance is further in a 600 f4. I have been to close to things for the camera to even focus…. I have the 400 2.8 and throw on the 1.4 tele for specific scenarios, but it rarely goes on my camera
It just takes practice - I shoot BIF with 800/840 all the time - often filling the frame pretty well as I do it. I have a short that shows how in less than a minute: th-cam.com/users/shortsrl79z3-2K6Q
I have a Canon 600mm f4 II and both Mark III teleconverters. (A combo that works very well.). Acquiring a BIF is difficult but becomes easier and easier with practice. I feel like 600 is easy at this point, 840 challenging and 1200mm damned hard but doable. Honestly I never purposely shoot at 1200mm when expecting BIF, it's the surprise bird or flock that comes into view when I'm shooting BOS. Oh and the way I practice is to try and point the lens at something on land (without using the viewfinder) then look at the view finder and correct. Repeat until getting it perfect and then find a new target. 100 reps can be done in a few minutes.
Im one of the new people in photography, im failing to see the point of this comparison. Both in purpose And price the 70-200mm and 600mm focial lengths are SO different. Its like comparing apples to pumpkins(not even oranges).
One of the best videos I've seen this year, Steve, and I've been taking pictures with interchangeable lenses since 1969. This makes it seem like spending $8,000 to $14,000 for a 400mm f/2.8 has some benefit. :) I would still take the 70 to 200 f/2.8 with me if I could.
Another great video, Steve. Thank you! This is not something that is obvious to most amateurs, despite some of the comments. This is something that must be taught (or learned the hard way!). Thanks for teaching it in a clear, concise way. You're the best!
It depends what I'm shooting - the two shots towards the end of the video were both full frame shots with the 300 2.8 and I have others as well. When I'm within range, it's the best. I don't use it all the time, but it is handy for some situations. Plus, it takes TCs really well so that's something to consider too.
This all makes perfect sense, but the 70-200/2.8 has huge portability and versatility advantages over a 600/4. When I’m travelling I’ll take the smaller lens any day of the week and accept the loss of resolution.
I already new this, but looking at it with so much detail, actual tests and numbers was an eye-opening experience. Something important, there is the AF system too, and the interaction is not as clear as it seems. In one hand having 5 times more light to AF will help a lot, on the other having a bigger subject will help too.
Hi Steve, Great video as it makes me think about the problem. What if I added a 1.4x teleconverter to the 300mm? Do you just do the math as if it was a 420mm lens with an extra stop? Same with the 2x converter?
Yeh, this is really important to understand, if you take a photo at 35mm f/4 on Full Frame and you find that background blur pleasing enough (which is 24mm f/2.6 APS-C equivalent, which many consider pretty darn good), that's like f/69 at 600mm, keeping the subject the same size in the frame. Working backwards, taking an f/6.3 600mm, if you wanted to match the background blur on a 35mm lens, you'd need an f/0.37 prime! I'd love some super compact f/16 tele zooms :)
Very clear explanation. I'd only toss out, if the math is still a bit complex, you could just consider the front element size as a proxy for the math. The bigger one should give you less noise and a softer background, assuming you will be taking the photo from the same spot. A 400 f/2.8, 600 f/4, 800 f/5.6 are all the same basic front element size. A 600 f/6.3 is slightly smaller than a 300 f/2.8 but larger than a 200 f/2.8. If you have both lenses, you can just look at them or put them next to each other to figure out which is larger. For completeness, this doesn't work at shorter focal lengths where the limit on the aperture is something other than the front element (like a 70-200 f/2.8 at 70). But long focal length lenses, that's pretty much what it is. And of course you might lose pixels w/ one choice vs another even with the same glass size (like 400 f/2.8 vs 800 f/5.6)
Tiny correction: The reason that the front element size comparison doesn't work for the 70-200 is that it's a zoom. It's not the focal length. It works for primes all the way down. I have a 35 1.4 and a 50 2.5 and you can definitely tell that the 35 gathers more light just by looking at the two. ;)
You are wrong, your human eye have around F/2.0, and anything below have less light gathering capability and do worse image by definition, so usual "almost perfect" desire is F/1.8 lens. Disadvantage is it huge heavy and $10000 range especially long focal distance, 800mm F1/8 must have obviously at least 800/1.8 = 444 mm diameter ! F/2.8 is only 2 times worse, and you seems to say it hype? You argue for 4x times worse solution like F/5.6? Aand I do not talk about resolution limit of diffraction (depend on aperture only, it is more astro topic but obviously affect crispness of any image)
@@AABB-px8lc Sigma produced a 200 to 500 mm f2.8 zoom. The only drawbacks were a 22K price tag, plus it weighed 34 pounds! I imagine not that many sold.
@@captaincrankysdock9730 exactly, and stupid astro/nanotech-lithography/military/cia keep pushing aperture as big as possible but few fricks call em "meh, it hype, F/8 or F5.6 is better"
Wow, i have never thought about that in theory! But in practice I have seen the result when cropping in from shorter, faster glass. I use my 180-600 on my Z6iii about 90% and only occasionally use my old 300/2,8 when I can get really close and "need" the f 2,8. Thanks for a great eye-opener!
A lot of photographers only think one dimensionally - DoF is determined by BOTH focal length and f stop. Couldn't agree with you more. Save the 70-200 2.8 for interior or closer up photography.
I use a 70-200 mm on an APS-C camera to good effect when the light is so low that focus lock with slower lenses is unobtainable. The field of view is 320mm. Always in places that allow me to get reasonably close to the subject.
I do a lot of pet photography so I can easily fill the frame with the 70-200 f/2.8. For wildlife I would rather use the longer lens as you said unless I was doing more of an environmental shot. Thanks for the video!!! This is great information!!!
the lowlight comparison is important for everybody to remember when comparing full frame to e.g. aps-c as well, where a similar misconception exists.. if you have two cameras identical in every way except one has a full frame sensor and the other has aps-c (but sensor technology the same. and pixel pitch the same), and you take a photo of a subject that is small enough in the frame to fit in the aps-c frame, then you will not have any better lowlight performance in the full frame camera. so for birding, where we rarely fill the frame, full frame wont give you better lowlight performance. it is only when you can actually fill the full frame taht you will gain lowlight performance over smaller sensors
Hello Steve! Great video ❤. Between just wish to ask one question as you speak about longer focal length then- Do MFTs lenses like Panasonic 100-400 mm f4-6.3 have an advantage? I understand in FF terms it’s 200-800 f8-12.6
There's no reason to use MFT for anything, ever. In apples to apples comparisons, meaning when you convert lens specs correctly between the systems, MFT is always either worse or more expensive or both compared to full frame alternatives. The only two situations where buying into MFT makes sense are a) you're so budget constrained that you have to go for the cheapest MFT option, which is so slow that no full frame counterpart exists. Your example is in the realm: There just isn't a full frame lens slow enough to "compete" with that 100-400. Or b) you physically can't carry anything larger or heavier than the absolute lightest and smallest MFT gear due to age or disability. There's no solution to b), for a) thought I'd recommend shopping used DSLR gear rather than buying into MFT.
I just returned from a trip to photograph orangutans. I brought the 600mm 6.3, the 100-400mm and the 135mm 1.8... Somehow the 70-200mm didn't end up in my bag probably because I wasn't expecting to get close enough. I was wrong! At times the orangutans came so close that the 135mm 1.8 showed what a fantastic lens it is. Not only in terms of sharpness and bokeh, but also considering how much light tall trees in the jungle absorb even on a bright day. I had not thought about this either ;). Next time the 100-400 will stay at home and the 70-200mm will be back in my back considering the encounters I had. Unless Nikon releases a 100-300mm 2.8 with build in TC ;) Thanks for a great video explaining this so clearly!
Great video and the timing of it is perfect since i’m looking for a lens for my Z8 for Wildlife Videography I’m leaning more towards 180-600 5.6-6.3 What’s your suggestions?
I find this comparison pretty strange. For one thing you are assuming that 600 mm would fill the frame where as 200 mm won’t. For a seasoned wildlife photographer, especially those shooting mammals, 70-200 is probably a more important lens owing to the field of. View and the perspective. The compressed look of long tele although providing background separation is cliched. The field of view of short tele is more unique. Unless one is always shooting portrait, the shallow depth of field is often more detrimental than not as it obscures the habitat of the subject. The way the video is pointing out, it would actually encourage amateur wildlife photographers to shun the shorter lenses when actually they should be embracing it. These lenses are tools and by using them one would learn which situation call for which. I am myself a wildlife photographer who has won several awards in highly acclaimed international contests and my super teleshots have produced 4-5 times less award winning shots as compared to wide angle and short tele 😂. Steve i adore your videos especially the technical ones but sorry i don’t agree with the way you present the facts here. Ciao.
Well said. Perception of depth in a picture and some context about the place the subject is shot in is much more interesting than a shot of a subject in a sea of blur.
There is nothing strange about this video nor is he making any assumptions. He was responding to those people who are considering using a shorter lense over a longer lense simply for the larger aperture. At no point did he say or suggest that people should only use 600mm lenses for wildlife photography. He is giving us the information we need in order decide for ourselves what lenses to use. If he had been asked about taking head shots of people and he made a video answering those questions, that wouldn't mean he was saying head shots are the only legitimate way to do portraits.
For photographing birds reach is the king. Rarely I’m able to come close enough to the subject to fill the frame with 70-200mm. Comparison makes sense as people don’t understand that bokeh is dependent on distance not just the aperture.
@@HomegrownHydra yeah, but he is only talking about background blur as if this is a primary thing when shooting with telelens. I use micro 4/3 system which gives more reach but also more depth of field focus so less background blur. I have a 75-300mm slow lens which gives me 600mm equivalent FOV as FF, but it' s really dificult to make sharp images at f/6.7 or f/8 (which gives DOF f/16 in FF terms). Now I have a 40-150mm f2.8 pro lens (80-300mm in FF terms) which is also weather sealed, same as my camera. Blur is the last of my problems, speed and weather sealing is what I care about most. I also have a 1.4 telecoverter that is also weather sealed.
Thanks Steve for the very enlightening video. No longer will I worry about using my Canon RF100-500 at the long end with an aperture of f7.1 and wishing I had got something faster.
The rf 100-500 is an incredible piece of engeniering, as sharp as a prime with the flexibility of a zoom, the slow aperture is not an issue with the great image stabilization of canon cameras paired with this lens plus all the Ai noise reduction options we have.
Thx again Steve, great info... several yrs now i use the Nikon 200-500 f5.6 and it is by far the best lens i ever had. Sharp as a razor and a steel at under 2k. its 5.6 @ 500mm is magic. Cropped to 750 the loss is marginal. Though its a heavy beast and u need muscle on a field day, but u get used to it and its not bad on a mono or tripod. The lens weight i compensated with light but strong carbon support gear....anyhow would luv 2 see more about this lens from you. cheers buddy
Absolutely brilliant… Knowledge and experience both at play (for which there is no substitute)… a differentiating factor from the up and coming young TH-cam crowd…
Very true Steve, I used to use an old EF400mm f/2.8 mostly with a 1.4x T.C attached to give me 560mm f/5.6 but after buying the RF 200-800mm f/6.3 - f/9 zoom I sold both my 400 2.8 and 300 2.8 as although sometimes the big primes had an advantage especially in a dark forest their minimum focus distance, size and weight meant I was missing too many shots and the freakish low light/high ISO performance of my Canon R6 ii means that even shots taken at ISO 12,800 or higher are plenty usable especially after running through DXO pure RAW 4. I also like to take my 135mm f/1.8 portrait lens along if there's a possibility of some extreme close ups of birds who tolerate or even welcome your presence. I do miss my big primes at times but my budget is limited so they had to go Cheers Noel
Can you create a video on how this can be used when using a micro four thirds in a 100-400mm lens vs a 70-202.8 or even a 150-600mm 6.3.? Thank you! You got my like and sub!
Thanks for the video. It's seeming to me that carrying around giant expensive glass just to get blurry backgrounds is getting less worth it, with what photoshop can do. Though sure, there are other reasons for fast lenses
That's a great explanation of the image quality. I wonder if the faster glass does help with other things like (mainly) autofocus? Probably harder to test, and maybe smaller subjects (relative to the frame) negate the advantage of more light to work with?
It can, but keep in mind that the larger your subject is in the viewfinder, the easier it is for AF to grab focus. At the end of the day, it's probably a wash most of the time.
The only valid use for myself to use a 70-200 or 100-300 f/2.8 on APS-C is barn owls. They usually show during sunset/night/sunrise and using a flash is basically a necessity. A brighter aperture requires a weaker flash and allows to shoot more till recharge is needed. plus that I don't want to vaporise the owl with 1/1 flash power. They are big and get close enough where these focal lengths work perfectly fine on APS-C. Now the lens must be actually that bright. f/# says nothing about transmission of course. Sitting in a cold barn by yourself, wind the wind, spooky sounds and practically in the dark you just want the photo. If the owl even decides to show. Lol
one missing factor is the shutter speed. the longer length lens will need a faster shutter speed to overcome shake for handheld. a faster shutter speed limits your light. so the shorter focal length may also have another light advantage being able to drop the shutter speed. or when keeping the shutter speeds the same between the two lenses, the shorter focal length has the potential for a sharper image minus the resolution loss if you have to crop.
That's incorrect. Cropping magnifies any camera shake that you had as well, so a 2x cropped shot at 200mm would show the exact same blur as an uncropped shot at 400mm, assuming the exact same level of camera shake. People just assume that the longer lens adds that issue because you've got a much higher level of sharpness compared to cropping, making blur more obvious when looking at images 1:1 in LR. That's not a fair comparison though. If you put the images side by side and zoom to the same subject size, the longer lens will always win out in subject detail (assuming the same level of shake/steadiness between shots).
@@youknowwho9247 Sure but you are more likely to have less shake with a shorter lighter lens so the shake would not stay consistant. Also often the shorter lens may have lower aperature rating allowing more light meaning you can increase your shutter speed to shave off more shake. In the long run we are talking small differences.
Great video as usual. The only thing you did not mention is that the focus ability and speed may be better with the 2.8 lens. That advantage may make the 2.8 lens the correct choice.
I think it depends - my 600PF is pretty quick and I don't think it would make much of a difference. Other glass, maybe, maybe not - too many variables :)
All your comments imply that you are after wild portraits, thats when the shallower depth of field comes into play. Not many photographers would use a 200 mm photo and then crop it to 600 mm equivalent to get a tight portrait. That would be suicidal. The short tele has its own significant place in wildlife photography. One has to know when to use it. Sometimes a subject is so far away that even a long tele shot cannot fill the frame and then the arguments put forward in this video about short tele applies to the long tele as well. A photographer by experience develops a notion of when to photograph and when not to.
Why do i always get the idea from comment sections on vids dealing with the '2.8' topic that there are all these people out there just dying for reasons to put fast glass down? Let me hazard a guess... deep down you'd love to have a bag stuffed full of the stuff, but the real-world you knows that you'll likely never be able to justify the investment? Does that cover 90% of the people who collect reasons for bagging fast glass? Mr Perry has presented a video that argues that in certain carefully constructed scenarios fast glass will provide no advantages. Mr Perry is also perfectly capable of doing similar to illustrate a range of scenarios where fast glass will get you results that no amount of tinkering with slower lenses will yield. Ultimately, for every stop you drop there'll be images you can't get - fast glass maximizes photographic opportunity. If those - call them 'images at the edge of possibility' - are not part of your repertoire, then having the fastest glass is of no consequence, but if those images are actually where you spend your photographic life, then fast glass is the making or breaking of what you do. Finally - if fast glass isn't a tool you need for your photography, i envy you.
While I can't speak to any of the motivations of the commenters, I can say my purpose for this video was simply to address the countless e-mails and comments I see where people think they can use a 200 2.8 or even 300 2.8 and overcome any low light or tangled background obstacle in their path. As you say, there are plenty of times a 2.8 lens is perfect and I own a bunch of them because they re advantageous. However, I see a lot of people mismatching their tools, so I wanted to help that segment :)
@@backcountrygallery Your teaching is a tremendous help to many - to me too as critters is just something I do i'm while waiting for some change in the sky for the shot i'm there to take. There was no criticism of what you're saying - the advantages of fast glass are wholly contingent on what you shoot - but some people take the 'you can do x,y,z with a 4' as a universal, and jump to coding fast glass packers as poseurs, wannabes, or dentists with a hobby (which some of us are). I listened closely to your presentation, hoping for a way out of the expense of fast glass that still allows me to make the most of the opportunities I chase. Sadly, no magic bullet - I hold the Laws of Physics and my preferred aesthetic responsible, not you. Thanks for all your valuable work - have a great day! Cheers.
One solution to this would be to carry the shorter, faster glass, say a 300mm f/2.8, with an excellent quality matching teleconverter. That would give you the 600mm reach with a f/5.6 aperture, and you would save some weight as well. The quality degradation would certainly be less than having to crop the shorter glass to that extent.
Steve - I would love to see you add this into your promised next video. For Sony shooters, the 300 2.8 x 2.0TC is an increasingly popular combo. I'd love to see your scientific and mathematical demonstration of what's really going on there, similar to how you did it here. Great video btw
Great video as always !! Short question, would the same kind of math apply if we consider different sensor size? So a 70-200mm f/2.8 mounted on an APS-C sensor would be equivalent to 200mm x1.5 = 300mm, f/2.8 x 1.5 = f/4.8 and same math for ISO? Assuming we fill the frame in the same way on a full frame and APS-C sensor.
Well, firstly 2.8 x 1.5 = 4.2, not 4.8 . And no, the same math does not apply for ISO because a) the relationship between noise and sensor area is linear (simplified) and b) the crop factor is the quare root of the multiplier of the sensor areas between the systems you're comparing. That's a complicated way of saying that as you go one size down with your sensors, your ISO performance gets one stop worse, not half a stop (log scale so this is all approximated; just because someone will inevitably get mad if I don't include this). To make this as simple as possible: When you're comparing systems, apply crop factor to focal length and aperture and multiply/divide ISO by crop factor squared (all rounded numbers). So 200mm, f/2.8, ISO 1600 on APS-C would look the same as 300mm, f/4, ISO 3200 on full frame. Or 150mm, f/2, ISO 800 on MFT.
This is so true and perfectly explained and demonstrated! Indeed, some of the most common mistakes. The same logic (or a lack of it) extends to how many people, even pros, talk about teleconverters: TC costs you F stops, you lose light. But no, compared to cropping, you don't! A true measure of how much light the lens collects per subject (given the subject is at the same distance) is the diameter of the lens front element - 600mm 6.3 is much wider than 200 mm 2.8, so it gathers more light. The big 400 2.8 and 600 4 are still in another category which is immediately obvious from how fat they are at the front. Funny, I've been to one French ornithological park recently where the openings in the hides were just wide enough for my 600 6.3 - so the big GM glass has no advantage there!
The argument about the TC cuts both ways though. Remember that it's an extra piece of kit that costs money and adds weight to your bag. Depending on your sensor, lens and TC combination, the loss of sharpness and contrast that the TC usually causes due to the extra glass in the way might make cropped shots and TC shots indistinguishable. In that case, cropping would be the better option, because all you get for the added cost and weight of the TC is a larger file with no extra detail. ;)
@@youknowwho9247 Agree, that could happen. However, I have tested a combination that is often discussed as problematic - Sony 200-600 mm (not a prime) with 1.4 TC on a1 (high megapixel body). Thus 2 factors that are supposed to diminish the usefulness of TC: zoom lens with a max 6.3 aperture and a high resolution sensor. Moreover, I compared the shots with and without TC using auto ISO, so let the ISO climb freely in the shot with TC to compensate for the increased F number. Despite all these, the shots with TC clearly showed more feather detail on a stationary bird than the shots without. My conclusion is that with this particular lens and body combination the 1.4TC is useful and better than crop. I expect it to be even more useful with a prime lens or on a lower MP body. Important note is that TC is useful only when the lens is zoomed in close to the max; if it's not the case, it's better to remove TC than to zoom out with TC.
I put myself into debt and depression chasing fast glass and “pro” gear. Turns out f/4 and P mode do just fine. I only wish I learned that lesson as a younger man.
A question / statement that keeps coming up is that most people would not really be comparing using a 70-200 2.8 vs a 600mm for wildlife work. However, I get the question all the time, but it's more like a chain of thought where someone has long glass but it's on the slow side, like a 600 6.3 of coms flavor. The light gets dim or the background is too busy and they start thinking that maybe they should opt for the faster 200mm 2.8 or 300mm 2.8 instead of the slower 600mm 6.3 since the 2.8 is so much faster. It's not so much that people are trying to use a 200mm 2.8 for general wildlife work instead of the 600mm; it's that they have both optics and the low light or busy backgrounds make them start to think about that F/2.8 sitting in the bag.
What people seem to forget is what the F stands for in F number - focal length. The depth of field doesn't care about F-number per se; at 200mm f/2.8 you have roughly a 71mm aperture, but 600mm at f/6.3 is above 95mm, while 14mm f/2.8 is a mere 5mm aperture opening! Acceptable depth of field at a given subject distance increases with the physical aperture opening, if you simplify a standard DOF formula it's quite obvious. My shorthand is to actually look at the front element on a telephoto - the bigger it is, the shallower I can get DOF at a given subject distance.
@@jec6613 Wikipedia says that approximately DOF = (2*u^2*N*c)/f^2 , where f=focal-length, N=f-number, u=distance, and c=circle-of-confusion. So focal length (or distance changes) have a squared effect on DOF, but f-number (f-stop) only linear. So going from a 200mm to 400mm lens at the same aperture will give 1/4 the DOF, but you would need to drop your f-number *4* stops (ea stop is a factor of sqrt(2)) to achieve the same change with f-stop alone.
Hi, excellent video. AF is also affected in a complicated way, for example having 5 times more light will help a lot, but having a bigger subject too. Could you run a comparison? thanks !!!
@@jec6613 Good rule of thumb :)
@@jaimeduncan6167 AF is tricky than that. Although the system is getting more light, the target is much smaller and tougher to lock onto. I think it's more of a wash than people think. If I can devise a way to test it, I may do just that.
Gotta remember the next time I'm out photographing grizzlies, use the 70-200 and move 3 times closer..............no, wait, keep using the 400 or 800 6.3.
Excellent Steve, thanks !!!
LOL :)
But then again, considering you'd have to open up a stop or so on the dark brown fur, wouldn't it be better to move closer with the 70 to 200 f2/.8? (Peace out, I'm just joking).
And remember to pet the fuzzy cow.
I love how you simplified a concept that seems to be challenging for many photographers. Thank you Steve.
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Got it right Steve because as you and others have pointed out in the past, and my own subjective observations to some extent, the longe lens compression wins even with considerably narrower apertures. Not having to crop, or nearly as much, is also a plus.
At 1:48 I got the answer correct. I took 600/200, we know that's 3.0. So then I multiplied 2.8 x 3.0 and got 8.4. The bokeh when cropped in 3x on that 2.8 will be more like 8.4, so I knew the lens with the lesser bokeh was the 70-200. Didn't know about the comparative ISO bit. Amazing video, loved it!
Blur = focal length / aperture
@@Mark-m6j8g Absolutely not. Background separation is about subject distance and the distance between the subject and the background more than anything else.
Thanks for explaining this Steve; very informative and it now makes me understand the high noise I get from cropping. Thanks again!
Hi Steve, I knew a lot of what you taught in this video. But I enjoyed watching it and the way you explained everything. TH-cam needs more no nonsense photography educators like you who know how to make beautiful images and also the technical aspects of the craft. I just subscribed to your channel.
Awesome, thank you!
This one video... I was awaiting this for years. So many people claiming 2.8 is the grail... I own a 500 pf and I am very happy with it. Thanks Steve.
A F2.8 remain an F2.8. An F4 remain an F4. 2 different apertures independently to the focal lenght. Made 2 different things.
@@julieng1312 I think Steve you’ve created a bit of confusion here by pushing a 70-200 f2.8 into what it’s not designed for. This video will be the most commented on & the most confusing to lots of people. @julieng1312, unfortunately an f2.8 will remain a reining king, while your & my 500mm f5.6 PF is a beauty but no match to 400mm f2.5 TC -Nikon engineers & all photographers know that
Pay them no mind. They would enjoy spending your money, probably more than they enjoyed spending their own. "Misery loves company", especially when the bills come in.
I've never seen anybody say to use a 70-200 f2.8 for a far away subject and crop. Literally nobody.
@@stretch90 People do that all the time, usually by putting a full frame 70-200 on a crop sensor body. The exact same logic applies.
I can close an f/2.8 i down to f/6.3. I can’t open an f/6.3 up to f/2.8 That’s why I prefer the fastest glass I can find for a given focal length
The 200mm focal length at f/2.8 has an aperture of 71.4mm, while the 600mm at f/6.3 has an aperture of 95.2mm. so as expected the larger aperture has the shallower depth of field.
Our host says @2:42 "Focal length as much on your on your depth of field as aperture, and that is the critical thing to remember." No, the critical thing to remember is that aperture is in millimeters. For the 600mm lens to get the same aperture as the 200mm at f/2.8 we would stop it down to f/8.4, and that will produce the same depth of field in this kind of test, that is tests of the same scene and camera position and we will crop and enlarge to the same field of view at the same display size.
Thank you for focusing your attention to the physical size of the apertures - the depth of field calculations are based on this - not the calculated aperture. (pun intended)
Excellent video as always Steve! Great reminder why filling the frame as much as possible is the way to go.
Wow, outstanding. Didn't know this, but it makes sense. Steve, i really appreciate how you educate us. Thanks, Bill
Despite having only 1 cup of coffee this morning, this is good information. Fill the frame or go slow.
That is why my all-time favorite lens is the 800 PF 6.3. I shot the 400.2.8 TC, but the 800 PF is never far from my kit. Excellent work, Steve!
I love that lens. Even though I have a 600 TC I tend to favor the 800 PF. If I know I’m gonna be in that focal range. It’s just so much lighter and easier to handle.
Good information to know, a slower lens in the field that has the reach you need is often better than a faster lens without the reach.
Really good one. The math is pretty simple. Learn something new every day. Thanks Steve.
Keep the 70-200mm for environmental shots & not push it for headshots unless close enough. That’s why you have a wider telephoto lens to begin with
And no need for them for environmental shot because you will need a smaller aperture to ensure the whole scene is in focus
@@MrDaveB123 Are you referring to the f2.8 lens is not useful for environmental shots? You’ve got it wrong, the fast f2.8 lens allows the sensor to focus more accurately. It closes to f11 (or whatever you set it up) millisecond before actually clicking the short so that you get your composed hyperfocal shot. This lens will be far superior than an f4 or f5.6 lens for that reason & of course if you need subject isolation in an environmental shot you’ve got beautiful bokeh to play with -not all environmental shots have to have everything in pin sharp focus like your phone camera. Hence the price you pay. All photographers & lens manufacturers know this…I thought
My example... I bought the (Z) 100-400 when it first came out, and it has been an amazing tool, illustrating your points exactly, even creating convincing "macro" shots. (My 70-200 2.8 is a great lens, but I use it less often, because of that.) We are all so lucky to have these tools today! :)
4:47 this is incredible informative! No fillers either, this is genius! Great tips!
The low-light situation as how I would apply it is to take photos of amphibians / insects at night time at close ranges. I would never shoot with the 200mm at the same distance at a 600mm but this was a good review / comparison none the less. Thank you for this.
Hi @Steve. Another fantastic and informative video. Thanks. I am waiting for the comparative video on 400 mm vs 600 mm. Hope you upload it soon.
I think it’ll be the first one in 2025
Excellent video! Your test shots and working through the math make your point clear. Much appreciated!
Excellent video Steve! So many photographers out there who do not understand the physics of optical systems.
This video has such practical importance for Wildlife Photographer. Thank you for making it!
Good luck in low light with your big lenses
I had the joy of viewing feeding lions at dusk close to our vehicle the 2.8 was invaluable
Predators come out to play as the sun goes down
I got the DoF comparison incorrect. A very useful, revealing video. Thanks
Something very important to consider when buying is difficulty acquiring your subject. Try shooting a bif with the 600 f4. It’s extremely hard to find the bird in the viewfinder. It’s even hard finding them in a tree most of the time. Also the minimum focusing distance is further in a 600 f4. I have been to close to things for the camera to even focus…. I have the 400 2.8 and throw on the 1.4 tele for specific scenarios, but it rarely goes on my camera
It just takes practice - I shoot BIF with 800/840 all the time - often filling the frame pretty well as I do it. I have a short that shows how in less than a minute: th-cam.com/users/shortsrl79z3-2K6Q
I have a Canon 600mm f4 II and both Mark III teleconverters. (A combo that works very well.). Acquiring a BIF is difficult but becomes easier and easier with practice. I feel like 600 is easy at this point, 840 challenging and 1200mm damned hard but doable. Honestly I never purposely shoot at 1200mm when expecting BIF, it's the surprise bird or flock that comes into view when I'm shooting BOS. Oh and the way I practice is to try and point the lens at something on land (without using the viewfinder) then look at the view finder and correct. Repeat until getting it perfect and then find a new target. 100 reps can be done in a few minutes.
This video was so great that I subscribed and saved it to my photo skills playlist!
Thank you!
Awesome! Thank you!
Thanks for the great video Steve! A add-on to the same topic regarding tele converters would be awesome! ❤
Perfect explained. Thank you!
This is a great video for new people to photograph and video.
Im one of the new people in photography, im failing to see the point of this comparison. Both in purpose And price the 70-200mm and 600mm focial lengths are SO different. Its like comparing apples to pumpkins(not even oranges).
I got it right! But I understand how depth of field works lol and how it’s not just about your aperture but distance and focal length.
One of the best videos I've seen this year, Steve, and I've been taking pictures with interchangeable lenses since 1969. This makes it seem like spending $8,000 to $14,000 for a 400mm f/2.8 has some benefit. :) I would still take the 70 to 200 f/2.8 with me if I could.
Now this is a perfect video in the truest sense, kudos to you!
Another great video, Steve. Thank you! This is not something that is obvious to most amateurs, despite some of the comments. This is something that must be taught (or learned the hard way!). Thanks for teaching it in a clear, concise way. You're the best!
Your production values are getting better and better!
Awesome as always 😊👍👌
Thanks Steve - Great content - as always !
Great video and a very practical way you compare long lenses
Steve, do you like your Sony 300mm f/2.8 for wildlife or do you find that it never "fills the frame" ?
It depends what I'm shooting - the two shots towards the end of the video were both full frame shots with the 300 2.8 and I have others as well. When I'm within range, it's the best. I don't use it all the time, but it is handy for some situations. Plus, it takes TCs really well so that's something to consider too.
Yes, te 400 2.8 would be roughly equivalent to a 600 f4, another beast. I'm happy so see someone analyzing this subject this way. I use it too.
Really interesting (and I even understood the math!) Explains a lot - thank you
This all makes perfect sense, but the 70-200/2.8 has huge portability and versatility advantages over a 600/4. When I’m travelling I’ll take the smaller lens any day of the week and accept the loss of resolution.
I already new this, but looking at it with so much detail, actual tests and numbers was an eye-opening experience. Something important, there is the AF system too, and the interaction is not as clear as it seems. In one hand having 5 times more light to AF will help a lot, on the other having a bigger subject will help too.
Hi Steve, Great video as it makes me think about the problem. What if I added a 1.4x teleconverter to the 300mm? Do you just do the math as if it was a 420mm lens with an extra stop? Same with the 2x converter?
Yup. When a lens has a TC, treat it like it's really that lens. For instance, if you add a 1.4TC to your 300 2.8, it's effectively a 420 F/4.
Very helpful for deciding which lens to bring.
Nice and concise, good video!
Moonpie
Very informative video. Thanks for sharing. A big LIKE for your video. Greetings from Singapore.
Yeh, this is really important to understand, if you take a photo at 35mm f/4 on Full Frame and you find that background blur pleasing enough (which is 24mm f/2.6 APS-C equivalent, which many consider pretty darn good), that's like f/69 at 600mm, keeping the subject the same size in the frame. Working backwards, taking an f/6.3 600mm, if you wanted to match the background blur on a 35mm lens, you'd need an f/0.37 prime!
I'd love some super compact f/16 tele zooms :)
Every video brings me new insights! Thanks, Steve.
Great video Steve!
Very clear explanation. I'd only toss out, if the math is still a bit complex, you could just consider the front element size as a proxy for the math. The bigger one should give you less noise and a softer background, assuming you will be taking the photo from the same spot. A 400 f/2.8, 600 f/4, 800 f/5.6 are all the same basic front element size. A 600 f/6.3 is slightly smaller than a 300 f/2.8 but larger than a 200 f/2.8. If you have both lenses, you can just look at them or put them next to each other to figure out which is larger.
For completeness, this doesn't work at shorter focal lengths where the limit on the aperture is something other than the front element (like a 70-200 f/2.8 at 70). But long focal length lenses, that's pretty much what it is. And of course you might lose pixels w/ one choice vs another even with the same glass size (like 400 f/2.8 vs 800 f/5.6)
Tiny correction: The reason that the front element size comparison doesn't work for the 70-200 is that it's a zoom. It's not the focal length. It works for primes all the way down. I have a 35 1.4 and a 50 2.5 and you can definitely tell that the 35 gathers more light just by looking at the two. ;)
I started photography two years ago but I knew that F2.8 is just hyped up for no reason. Thank you so much Steve for this video
You are wrong, your human eye have around F/2.0, and anything below have less light gathering capability and do worse image by definition, so usual "almost perfect" desire is F/1.8 lens. Disadvantage is it huge heavy and $10000 range especially long focal distance, 800mm F1/8 must have obviously at least 800/1.8 = 444 mm diameter ! F/2.8 is only 2 times worse, and you seems to say it hype? You argue for 4x times worse solution like F/5.6? Aand I do not talk about resolution limit of diffraction (depend on aperture only, it is more astro topic but obviously affect crispness of any image)
@@AABB-px8lc Sigma produced a 200 to 500 mm f2.8 zoom. The only drawbacks were a 22K price tag, plus it weighed 34 pounds! I imagine not that many sold.
@@captaincrankysdock9730 exactly, and stupid astro/nanotech-lithography/military/cia keep pushing aperture as big as possible but few fricks call em "meh, it hype, F/8 or F5.6 is better"
Well illustrated Steve !
Wow, i have never thought about that in theory! But in practice I have seen the result when cropping in from shorter, faster glass. I use my 180-600 on my Z6iii about 90% and only occasionally use my old 300/2,8 when I can get really close and "need" the f 2,8. Thanks for a great eye-opener!
So based on this calculation a 400 F2.8 x 1.5 = F4.2, you can say that in general a 600 F4 is "a faster lens" then a 400 F2.8 ?
They're about the same, except the 400 can shoot wider when you're closer while the 600 gets you more resolution when you're further away.
A lot of photographers only think one dimensionally - DoF is determined by BOTH focal length and f stop. Couldn't agree with you more. Save the 70-200 2.8 for interior or closer up photography.
And distance too, so there are three factors to depth of field.
Very interesting. At last someone intelligent that understands how lenses work doing a comparison the correct way.
Thanks, Steve for a really interesting video.
I use a 70-200 mm on an APS-C camera to good effect when the light is so low that focus lock with slower lenses is unobtainable. The field of view is 320mm. Always in places that allow me to get reasonably close to the subject.
I do a lot of pet photography so I can easily fill the frame with the 70-200 f/2.8. For wildlife I would rather use the longer lens as you said unless I was doing more of an environmental shot. Thanks for the video!!! This is great information!!!
the lowlight comparison is important for everybody to remember when comparing full frame to e.g. aps-c as well, where a similar misconception exists.. if you have two cameras identical in every way except one has a full frame sensor and the other has aps-c (but sensor technology the same. and pixel pitch the same), and you take a photo of a subject that is small enough in the frame to fit in the aps-c frame, then you will not have any better lowlight performance in the full frame camera. so for birding, where we rarely fill the frame, full frame wont give you better lowlight performance. it is only when you can actually fill the full frame taht you will gain lowlight performance over smaller sensors
Mind blowing.... thanks for some very valuable information!!! You're awesome!!
Thanks, Steve! Prompted my mathematics anxiety, but I persevered and got the lesson! :)
LOL, you and me both!
Well done, Steve
Hello Steve! Great video ❤. Between just wish to ask one question as you speak about longer focal length then-
Do MFTs lenses like Panasonic 100-400 mm f4-6.3 have an advantage?
I understand in FF terms it’s 200-800 f8-12.6
There's no reason to use MFT for anything, ever. In apples to apples comparisons, meaning when you convert lens specs correctly between the systems, MFT is always either worse or more expensive or both compared to full frame alternatives. The only two situations where buying into MFT makes sense are a) you're so budget constrained that you have to go for the cheapest MFT option, which is so slow that no full frame counterpart exists. Your example is in the realm: There just isn't a full frame lens slow enough to "compete" with that 100-400. Or b) you physically can't carry anything larger or heavier than the absolute lightest and smallest MFT gear due to age or disability. There's no solution to b), for a) thought I'd recommend shopping used DSLR gear rather than buying into MFT.
Great video Steve now I am smarter than I was this morning. Thank You
Thank you Steve! Easy to understand and really important info. Common sense, surely, but now it is proven. Thanks again.
I just returned from a trip to photograph orangutans. I brought the 600mm 6.3, the 100-400mm and the 135mm 1.8... Somehow the 70-200mm didn't end up in my bag probably because I wasn't expecting to get close enough. I was wrong! At times the orangutans came so close that the 135mm 1.8 showed what a fantastic lens it is. Not only in terms of sharpness and bokeh, but also considering how much light tall trees in the jungle absorb even on a bright day. I had not thought about this either ;). Next time the 100-400 will stay at home and the 70-200mm will be back in my back considering the encounters I had. Unless Nikon releases a 100-300mm 2.8 with build in TC ;)
Thanks for a great video explaining this so clearly!
Great video and the timing of it is perfect since i’m looking for a lens for my Z8 for Wildlife Videography
I’m leaning more towards 180-600 5.6-6.3
What’s your suggestions?
I am from India & you are truly an amazing person. Appreciate your work🙏
I find this comparison pretty strange. For one thing you are assuming that 600 mm would fill the frame where as 200 mm won’t. For a seasoned wildlife photographer, especially those shooting mammals, 70-200 is probably a more important lens owing to the field of. View and the perspective. The compressed look of long tele although providing background separation is cliched. The field of view of short tele is more unique. Unless one is always shooting portrait, the shallow depth of field is often more detrimental than not as it obscures the habitat of the subject. The way the video is pointing out, it would actually encourage amateur wildlife photographers to shun the shorter lenses when actually they should be embracing it. These lenses are tools and by using them one would learn which situation call for which. I am myself a wildlife photographer who has won several awards in highly acclaimed international contests and my super teleshots have produced 4-5 times less award winning shots as compared to wide angle and short tele 😂. Steve i adore your videos especially the technical ones but sorry i don’t agree with the way you present the facts here. Ciao.
Well said. Perception of depth in a picture and some context about the place the subject is shot in is much more interesting than a shot of a subject in a sea of blur.
There is nothing strange about this video nor is he making any assumptions. He was responding to those people who are considering using a shorter lense over a longer lense simply for the larger aperture. At no point did he say or suggest that people should only use 600mm lenses for wildlife photography. He is giving us the information we need in order decide for ourselves what lenses to use. If he had been asked about taking head shots of people and he made a video answering those questions, that wouldn't mean he was saying head shots are the only legitimate way to do portraits.
There is no rule for background subject Vs blur. It depends on what the photographer wants to achieve and both have their place.
For photographing birds reach is the king. Rarely I’m able to come close enough to the subject to fill the frame with 70-200mm. Comparison makes sense as people don’t understand that bokeh is dependent on distance not just the aperture.
@@HomegrownHydra yeah, but he is only talking about background blur as if this is a primary thing when shooting with telelens. I use micro 4/3 system which gives more reach but also more depth of field focus so less background blur. I have a 75-300mm slow lens which gives me 600mm equivalent FOV as FF, but it' s really dificult to make sharp images at f/6.7 or f/8 (which gives DOF f/16 in FF terms). Now I have a 40-150mm f2.8 pro lens (80-300mm in FF terms) which is also weather sealed, same as my camera. Blur is the last of my problems, speed and weather sealing is what I care about most. I also have a 1.4 telecoverter that is also weather sealed.
Thank you Steve! Very interesting...and educational.
Thanks Steve for the very enlightening video. No longer will I worry about using my Canon RF100-500 at the long end with an aperture of f7.1 and wishing I had got something faster.
Don't take the wrong lesson here though - fast glass under the right circumstances is GREAT!
@@backcountrygallery Certainly , without a doubt Steve.
The rf 100-500 is an incredible piece of engeniering, as sharp as a prime with the flexibility of a zoom, the slow aperture is not an issue with the great image stabilization of canon cameras paired with this lens plus all the Ai noise reduction options we have.
Great video Steve, Have you tried the Z 400 f2.8 with the 2x tele? I hear it works pretty good.
Great video, thank you Steve! What's the math on the 70-200 f2.8 with a 2.0 TC?
Thx again Steve, great info... several yrs now i use the Nikon 200-500 f5.6 and it is by far the best lens i ever had. Sharp as a razor and a steel at under 2k. its 5.6 @ 500mm is magic. Cropped to 750 the loss is marginal. Though its a heavy beast and u need muscle on a field day, but u get used to it and its not bad on a mono or tripod. The lens weight i compensated with light but strong carbon support gear....anyhow would luv 2 see more about this lens from you. cheers buddy
Absolutely brilliant… Knowledge and experience both at play (for which there is no substitute)… a differentiating factor from the up and coming young TH-cam crowd…
Very interesting analysis and very helpful.❤
Love that math!... Very nice computations... focal length and a good technique as well good ISO management at camera will help along the road!
Don't forget today's image stabilization. At 400 mm+... tripod, what's a tripod?
Very true Steve,
I used to use an old EF400mm f/2.8 mostly with a 1.4x T.C attached to give me 560mm f/5.6 but after buying the RF 200-800mm f/6.3 - f/9 zoom I sold both my 400 2.8 and 300 2.8 as although sometimes the big primes had an advantage especially in a dark forest their minimum focus distance, size and weight meant I was missing too many shots and the freakish low light/high ISO performance of my Canon R6 ii means that even shots taken at ISO 12,800 or higher are plenty usable especially after running through DXO pure RAW 4. I also like to take my 135mm f/1.8 portrait lens along if there's a possibility of some extreme close ups of birds who tolerate or even welcome your presence.
I do miss my big primes at times but my budget is limited so they had to go
Cheers
Noel
Great explainer Steve! Thank you as always.
Great video. Thank you.
Can you create a video on how this can be used when using a micro four thirds in a 100-400mm lens vs a 70-202.8 or even a 150-600mm 6.3.? Thank you! You got my like and sub!
Does this photograpy math work the same If we take the crop factor of an aps-c to "compare" an apsc and a full frame instead of 2 differents lenses
Thanks for the video. It's seeming to me that carrying around giant expensive glass just to get blurry backgrounds is getting less worth it, with what photoshop can do. Though sure, there are other reasons for fast lenses
Great Video Thanks...
That's a great explanation of the image quality. I wonder if the faster glass does help with other things like (mainly) autofocus? Probably harder to test, and maybe smaller subjects (relative to the frame) negate the advantage of more light to work with?
It can, but keep in mind that the larger your subject is in the viewfinder, the easier it is for AF to grab focus. At the end of the day, it's probably a wash most of the time.
The only valid use for myself to use a 70-200 or 100-300 f/2.8 on APS-C is barn owls.
They usually show during sunset/night/sunrise and using a flash is basically a necessity.
A brighter aperture requires a weaker flash and allows to shoot more till recharge is needed.
plus that I don't want to vaporise the owl with 1/1 flash power.
They are big and get close enough where these focal lengths work perfectly fine on APS-C.
Now the lens must be actually that bright. f/# says nothing about transmission of course.
Sitting in a cold barn by yourself, wind the wind, spooky sounds and practically in the dark you just want the photo. If the owl even decides to show. Lol
one missing factor is the shutter speed. the longer length lens will need a faster shutter speed to overcome shake for handheld. a faster shutter speed limits your light. so the shorter focal length may also have another light advantage being able to drop the shutter speed. or when keeping the shutter speeds the same between the two lenses, the shorter focal length has the potential for a sharper image minus the resolution loss if you have to crop.
i was desperately looking for this comment. Leaving the shutter speed out of the equation is like not telling the whole truth, kinda disingenuous imo
Use a tripod or some other support - it's the best way to get around the problem and have the best overall image quality.
@@backcountrygallery yeah and politely ask the animal to stay still :)
That's incorrect. Cropping magnifies any camera shake that you had as well, so a 2x cropped shot at 200mm would show the exact same blur as an uncropped shot at 400mm, assuming the exact same level of camera shake. People just assume that the longer lens adds that issue because you've got a much higher level of sharpness compared to cropping, making blur more obvious when looking at images 1:1 in LR. That's not a fair comparison though. If you put the images side by side and zoom to the same subject size, the longer lens will always win out in subject detail (assuming the same level of shake/steadiness between shots).
@@youknowwho9247 Sure but you are more likely to have less shake with a shorter lighter lens so the shake would not stay consistant. Also often the shorter lens may have lower aperature rating allowing more light meaning you can increase your shutter speed to shave off more shake. In the long run we are talking small differences.
Great video as usual. The only thing you did not mention is that the focus ability and speed may be better with the 2.8 lens. That advantage may make the 2.8 lens the correct choice.
I think it depends - my 600PF is pretty quick and I don't think it would make much of a difference. Other glass, maybe, maybe not - too many variables :)
Provided you keep to frame filling shots. Don’t masquerade it like a big prime lens which I am sure most of us don’t
No if you can not fill the frame 2.8 does nothing. what is wrong with a tad higher ISO with modern day cameras and software?
All your comments imply that you are after wild portraits, thats when the shallower depth of field comes into play. Not many photographers would use a 200 mm photo and then crop it to 600 mm equivalent to get a tight portrait. That would be suicidal. The short tele has its own significant place in wildlife photography. One has to know when to use it. Sometimes a subject is so far away that even a long tele shot cannot fill the frame and then the arguments put forward in this video about short tele applies to the long tele as well. A photographer by experience develops a notion of when to photograph and when not to.
wow i've learned so much today. thank you
Why do i always get the idea from comment sections on vids dealing with the '2.8' topic that there are all these people out there just dying for reasons to put fast glass down? Let me hazard a guess... deep down you'd love to have a bag stuffed full of the stuff, but the real-world you knows that you'll likely never be able to justify the investment? Does that cover 90% of the people who collect reasons for bagging fast glass? Mr Perry has presented a video that argues that in certain carefully constructed scenarios fast glass will provide no advantages. Mr Perry is also perfectly capable of doing similar to illustrate a range of scenarios where fast glass will get you results that no amount of tinkering with slower lenses will yield. Ultimately, for every stop you drop there'll be images you can't get - fast glass maximizes photographic opportunity. If those - call them 'images at the edge of possibility' - are not part of your repertoire, then having the fastest glass is of no consequence, but if those images are actually where you spend your photographic life, then fast glass is the making or breaking of what you do. Finally - if fast glass isn't a tool you need for your photography, i envy you.
While I can't speak to any of the motivations of the commenters, I can say my purpose for this video was simply to address the countless e-mails and comments I see where people think they can use a 200 2.8 or even 300 2.8 and overcome any low light or tangled background obstacle in their path. As you say, there are plenty of times a 2.8 lens is perfect and I own a bunch of them because they re advantageous. However, I see a lot of people mismatching their tools, so I wanted to help that segment :)
@@backcountrygallery Your teaching is a tremendous help to many - to me too as critters is just something I do i'm while waiting for some change in the sky for the shot i'm there to take. There was no criticism of what you're saying - the advantages of fast glass are wholly contingent on what you shoot - but some people take the 'you can do x,y,z with a 4' as a universal, and jump to coding fast glass packers as poseurs, wannabes, or dentists with a hobby (which some of us are). I listened closely to your presentation, hoping for a way out of the expense of fast glass that still allows me to make the most of the opportunities I chase. Sadly, no magic bullet - I hold the Laws of Physics and my preferred aesthetic responsible, not you. Thanks for all your valuable work - have a great day! Cheers.
@@luzr6613 Thanks for the kind words :)
One solution to this would be to carry the shorter, faster glass, say a 300mm f/2.8, with an excellent quality matching teleconverter. That would give you the 600mm reach with a f/5.6 aperture, and you would save some weight as well. The quality degradation would certainly be less than having to crop the shorter glass to that extent.
It’s a great way to go.
Steve - I would love to see you add this into your promised next video. For Sony shooters, the 300 2.8 x 2.0TC is an increasingly popular combo. I'd love to see your scientific and mathematical demonstration of what's really going on there, similar to how you did it here. Great video btw
Ooh, was hoping you'd do the 400 2.8 vs 600 f4! Great video Steve
It's one I've been wanting to do for a long time - I have BOTH Nikon and Sony sets now!
Great video as always !! Short question, would the same kind of math apply if we consider different sensor size? So a 70-200mm f/2.8 mounted on an APS-C sensor would be equivalent to 200mm x1.5 = 300mm, f/2.8 x 1.5 = f/4.8 and same math for ISO? Assuming we fill the frame in the same way on a full frame and APS-C sensor.
It mostly applies- but technically differences in sensor performance might make minor differences here and there for ISO performance.
Well, firstly 2.8 x 1.5 = 4.2, not 4.8 . And no, the same math does not apply for ISO because a) the relationship between noise and sensor area is linear (simplified) and b) the crop factor is the quare root of the multiplier of the sensor areas between the systems you're comparing. That's a complicated way of saying that as you go one size down with your sensors, your ISO performance gets one stop worse, not half a stop (log scale so this is all approximated; just because someone will inevitably get mad if I don't include this). To make this as simple as possible: When you're comparing systems, apply crop factor to focal length and aperture and multiply/divide ISO by crop factor squared (all rounded numbers). So 200mm, f/2.8, ISO 1600 on APS-C would look the same as 300mm, f/4, ISO 3200 on full frame. Or 150mm, f/2, ISO 800 on MFT.
Excellent advice!
This is so true and perfectly explained and demonstrated! Indeed, some of the most common mistakes. The same logic (or a lack of it) extends to how many people, even pros, talk about teleconverters: TC costs you F stops, you lose light. But no, compared to cropping, you don't! A true measure of how much light the lens collects per subject (given the subject is at the same distance) is the diameter of the lens front element - 600mm 6.3 is much wider than 200 mm 2.8, so it gathers more light. The big 400 2.8 and 600 4 are still in another category which is immediately obvious from how fat they are at the front. Funny, I've been to one French ornithological park recently where the openings in the hides were just wide enough for my 600 6.3 - so the big GM glass has no advantage there!
The argument about the TC cuts both ways though. Remember that it's an extra piece of kit that costs money and adds weight to your bag. Depending on your sensor, lens and TC combination, the loss of sharpness and contrast that the TC usually causes due to the extra glass in the way might make cropped shots and TC shots indistinguishable. In that case, cropping would be the better option, because all you get for the added cost and weight of the TC is a larger file with no extra detail. ;)
@@youknowwho9247 Agree, that could happen. However, I have tested a combination that is often discussed as problematic - Sony 200-600 mm (not a prime) with 1.4 TC on a1 (high megapixel body). Thus 2 factors that are supposed to diminish the usefulness of TC: zoom lens with a max 6.3 aperture and a high resolution sensor. Moreover, I compared the shots with and without TC using auto ISO, so let the ISO climb freely in the shot with TC to compensate for the increased F number. Despite all these, the shots with TC clearly showed more feather detail on a stationary bird than the shots without. My conclusion is that with this particular lens and body combination the 1.4TC is useful and better than crop. I expect it to be even more useful with a prime lens or on a lower MP body. Important note is that TC is useful only when the lens is zoomed in close to the max; if it's not the case, it's better to remove TC than to zoom out with TC.
I put myself into debt and depression chasing fast glass and “pro” gear. Turns out f/4 and P mode do just fine. I only wish I learned that lesson as a younger man.
People fall to multiply the f-stop.
WELL DONE