How you explain every topic with all these information and cover all that in less than 10 minutes shows the years of learning and how much effort that you did to know all of these things. I learned so much from you. Thank you for your hard work Gerald, You are a LEGEND.
This is unbelievable. Nobody would believe this. I was searching t stop vs f stop and reading an article when I received the notification for this video! This really is unbelievable.
Simon Patterson I don’t think you quite understand what I’m talking about. I was confused between Samyang’s 14mm f/2.8 and T3.1 and was googling to know what exactly a T stop is and what the differences are between these values. I’m subscribed to Gerald’s channel and I received the notification as I was opening one of the search results ie. the video was uploaded while I was searching about the same topic. Coincidence yes but really unbelievable. Is Gerald an alien? The next Camera conspiracies video should be about that 😀
@@rammadhavmohan1890 ah, gotcha, I see what you meant now. That is a cool coincidence. Gee it was well explained, too, eh... clear and concise as Gerald always does.
I never get tired of saying another well presented informative video. You keep presenting useful information. Thank you . Look forward to your 50K video which you should hit by tomorrow.
Another great explanation video. Thanks! Something I haven't found much info on, or any clear comparisons is a comparison of dng file versus native raw files from camera brands (this is useful if someone does not want to upgrade to newer lightroom version just to have access to the native raw files from camera brands). Cheers!
This is a very simplistic & accurate explanation, thank you. This is a highly volatile topic & the subject for many photographer trolls to rage out over; hope you avoid that. It makes sense to me, but I've used both photography lenses & cine lenses for narrative work & have visually seen the inconsistencies.
I love this video! I'm scripting something similar (but still different enough) about the differences between cinema and stills glass, but this nails the calculation so perfectly. You are an inspiration, mate.
I love your explanation videos! It really helped me in making a camera buying decision (now just need to save up). I can't wait to see more content like this. You are AWESOME!!!
Old school guy, and old too! Never occurred to me before, use my gear for mostly documenting art work etc., kinda clinical in a way, because my modern gear allows so many interesting things to to in regards to other avenues, why not, very well explained, Thanks!
No, Thanks you, the ability to explain to others without the use of crayons is no simple feat, the math is easy, I hope, but too encourage others out of the blue, rare, hope you teach others,
I think my head just exploded! Man you are smart! I went from thinking it would be cool to hang out, to now thinking that I would be reticent to open my mouth ;) Kidding aside, great stuff as usual Gerald. Hey here's how you can lighten it up. "I'm Gerald undone and I'm not wearing pants"
You are Wikipedia of sensors and optics. I love your videos because they are straight to the point and simple to follow and always learn something out of it. Just a small suggestion for this video though to make it consistent with notations you've used. At 0:36 f/N=D where f = focal length, N = f-number and D = Diameter of entrance pupil. But at 1:40 T=f/N/sqrt(trans%) where I understand that you meant f-stop (e.g. f/2.8) by f/N but I got confused as you already used f for focal length before. I initially thought you meant D by f/N. Maybe you could write T=N/sqrt(trans%) or T=f/D/sqrt(trans%) to be consistent.
I know what you mean, but D needs to be measured in mm, where f-stop is a ratio. So in f/n, f still is focal length, but it's only the N that really matters. I suppose N from earlier would have been better. I was just trying to express it as it's written f/2.8, etc. But I think you know what I mean. Glad you're diggin' the videos. Appreciate the comment.
Nicely explained. Even through a single pane of optically clear glass, less than 100% of the incident light is transmitted. At least 4% is lost to reflection. Can you imagine what happens in a zoom lens with 14 or 15 elements, coatings and all?
Some older macro lenses don't have constant transmission at a given f-stop. They require positive compensation the closer the camera is to the subject.
I like this video and I agree the the f and t stop shouldn't be seen as adversarial, but, manufactures should put both f and t stop 'on the can'. I do want to know which prime is going to give me a brighter image because I shoot photo and video, it also can give a clue to which lens has better micro contrast and will help me bring up the shadows with less noise and easier. I actually consider this as part of my purchase, especially in a system that has a gluttony of lenses to choose from like MFT.
The best explanation of t and f on youtube! thanks. Do you have plans to do a video regarding AF systems? what is the main difference and which one is better for video?
Nice explanation. It's concise and no more complicated than it needs to be. Have you, or anyone else for that matter, seen any tables of light transmission values of common or popular stills lenses? With more videographers using DSLR and mirrorless cameras, and the standard stills lenses that come with them, I'd think a table like that would be useful. thanks, richard hargrove -- “Everything that needs to be said has already been said. But since no one was listening, everything must be said again.” - André Gide
It would be nice to have a simplified resource for that. DxOMark measures it for the lenses they test, but there are a lot of lenses that aren't covered.
Hello... in astronomy we talk about light in terms of diameter of the mirror... so 6 inches, 8 inches... because we are all about gathering light from the night sky. Why is this not possible in photography? Wouldn't a larger diameter lens take in more light than a smaller lens? I've seen the tiniest of pancake lens... with the largest of apertures... how can they be good at taking in light? Thanks for the opportunity to vent here! Your video is very informative!
Hi, finally an explaination. What not clear is this: Sony web site, two lenses: about the first just says f/1.4; the second f/2.8 T/5.6 (if I recall the values). So why does Sony declare the T value only for the second one? How am I supposed to find out the T for the first? Regards.
What would be a practical-ish way to get the transmission data for fstop lenses? Nothing laboratory exact, but say I know the transmission data for a specific lens I have, and I want to figure out the transmission data for a vintage lens. How do I go about calculating the transmission by comparing shots from both lenses in a controlled lighting situation to get a really rough estimate of where the transmission for that lens might be, give or take a few percent.
If one is looking for a fast lens, lets say thinking of purchasing a f1.4 factor lens then it would be helpful to know the T stop when comparing lenses, wanting the "fastest" lens. So what is faster, the Canon 50 1.4, Sigma 50 1.4, Tamron 50 1.4, etc.
So... Is there some third party or photo club, etc, that has measured the max T-stop of common photography lenses? (I'm amazed at what clubs and interest groups have done in other cases, and this seems useful.)
I have no idea in about 80% of what you said in that video. 😄😄 However, if I focus I will eventually get the hang of it. In the meantime...What is the equivalent of t2.2 in f stop? Thanks much.
On a zoom lens, is the T-stop pretty much fixed throughout the zoom range or is it changing? It seems like the T-stop should be pretty much fixed as the light needs to go through the same number of elements regardless of the chosen focal length..... Is there a website you know of that compares T-stops of various lenses used in photography? Thanks!
Great video. Question: If one needed to convert from t-stops to f-stops on a cinema lens to calculate the depth of field, where would you find information on the "transmittance percentage" of a lens? I've been looking and can't seem to find any information on this. Is it called something else? Is converting from t to f using the equation you mentioned required or could you just estimate by rounding down to the nearest f-stop (as you also mentioned)? Is there a different way of calculating depth of field with just the t-stop and without needing to convert to f-stops?
I just bought my first cinema lens, which is a Rokinon 85mm. I usually use a light meter to check my exposure but I don't know how to convert the f stop to the T stop. Help.
great info... hey now I'm curious , I have a Mitakon-Zhongyi 35mm f/0.95 II speedmaster lens for Sony E-mount.... would you be able to tell me what the T-stop for that lens would be ?
Mitakon 50 f/0.95 lens is near T1.4 at wide open. So, this lens has surprisingly low light transmission value compared to f-stop. I heard E-mount has small mount diameter that cause light loss. This would be the reason why Nikon Z and Canon EF/RF mount has bigger mount diameter.
Isn't there also a kind of maximum transition or sensitivity by the sensor - and how would they relate? Does either lens or sensor limit the t-stop by it's own capabilitiy or is one relevant for the other?
Well sensors can always receive more light until they're clipped. So if you have a high enough shutter speed you should be able to keep increasing the T-stop. There are design limitations though that can occur based on mount size and flange shape where transmission goes down because of the body.
I recall it was something about the photodiodes on the sensors themselves, someone claiming that they would limit the light transmission no matter what wide aperture lens you would use.
I had a question that I can't find the answer to: I use the Sony a7iii and when I change the aperture in photo mode, I can hear a slight bit of noise from the aperture blades moving. If I then put it into video mode there is absolutely no noise when changing the aperture. This happens across multiple lenses and it just has me curious as to why, if Sony has the capability to make the aperture silent in video, it doesn't do so for photos? Other people have suggested the auto focus is the cause but it happens when auto focus is turned off.
Gerald, have you ever tried a gentle oil to put in your hair to keep the flyaways at bay? I use pure vitamin E oil and it feels wonderful in my equal-length hair.
@@geraldundone Hahaha, it's that 4k super sharp video that helped those flyaways get noticed. On a bad hair day - film with a potato (or downscale to minecraft resolution).
There's no way of knowing without measuring. That's his whole point. Although at f1.4 it would have to have terrible light transmittance to not beat T1.9. It's probably T1.6 or so.
You consistently pack 10-plus minutes of information into 4 minutes of succinct and entertaining goodness.
Thanks a bunch! Glad you're diggin' the pace.
How you explain every topic with all these information and cover all that in less than 10 minutes shows the years of learning and how much effort that you did to know all of these things.
I learned so much from you.
Thank you for your hard work Gerald, You are a LEGEND.
Big compliment. Really appreciated. Thanks so much! 😃🙏
Gerald Undone + Beethoven's 5th intro = "What is happening everybody; I'm Gerald Un-dun dun dun duuuun"
Love this one!
for the love of everything good in this world...DEFINITELY consider this one lol
YAS, he did it !
@@billyboy_45 Wait, what? Are you seeing early releases of his vids?
I just sang this in my bathroom 🤣
I love this guy, I've taken photos for years, even made a living from it and after watching Gerald I think I now know nothing ~
Ha. I'm sure you're just being modest, but I appreciate the kind words. 😃🙏
Haven’t we all been there @theUKToday 😅
Literally. This guy can teach anyone anything. That is a rare talent
Wow! Big compliment. Thanks a lot for that.
This is unbelievable. Nobody would believe this. I was searching t stop vs f stop and reading an article when I received the notification for this video! This really is unbelievable.
Google is tracking everything you do online, and feeding you particular information as a result? Nobody will ever believe that! 😂
Ha! Fun coincidence. 😃👍
Simon Patterson I don’t think you quite understand what I’m talking about. I was confused between Samyang’s 14mm f/2.8 and T3.1 and was googling to know what exactly a T stop is and what the differences are between these values. I’m subscribed to Gerald’s channel and I received the notification as I was opening one of the search results ie. the video was uploaded while I was searching about the same topic. Coincidence yes but really unbelievable. Is Gerald an alien? The next Camera conspiracies video should be about that 😀
Gerald Undone Another great video. Thanks. And you compared the same f/2.8 and T 3.1 values I was looking for. You just saved a lot of my time! 🙏🏻
@@rammadhavmohan1890 ah, gotcha, I see what you meant now. That is a cool coincidence. Gee it was well explained, too, eh... clear and concise as Gerald always does.
I swear with these educational videos, you win the internet
That's very kind. Thank you. 😃
No one explains it like you buddy.. hat's off.
Thanks, Adolfo! Cheers.
Gerald the kind of guy to get Philip Bloom to comment on his stuff.
😃🤓👍
If i watch while scrolling in the comments....am i listening to a podcast?
I never get tired of saying another well presented informative video. You keep presenting useful information. Thank you . Look forward to your 50K video which you should hit by tomorrow.
And I never get tired of your encouraging comments! Thanks again, Phil. 😃
I LOVE your openings sentences
Plz don't stop doing that
Thanks! You got it.
Maybe next time start with
"Roses are red
violets are blue
I know some stuff
And I will teach you"
Nice job Gerald! That's the BEST explanation of f/t stops I've ever seen. Congrats.
This video was extremely informative. *Full stop*
Thank you! I'm glad to hear that. 😃🙏
Gerald
Thank you for existing
Another great explanation video. Thanks! Something I haven't found much info on, or any clear comparisons is a comparison of dng file versus native raw files from camera brands (this is useful if someone does not want to upgrade to newer lightroom version just to have access to the native raw files from camera brands). Cheers!
This is a very simplistic & accurate explanation, thank you.
This is a highly volatile topic & the subject for many photographer trolls to rage out over; hope you avoid that.
It makes sense to me, but I've used both photography lenses & cine lenses for narrative work & have visually seen the inconsistencies.
You should have used a chalkboard!
They don't make them in purple! 😜
@@geraldundone you can actually get chalkboard paint in pretty much any color you want nowadays, or just make your own with recipes available online.
I love this video! I'm scripting something similar (but still different enough) about the differences between cinema and stills glass, but this nails the calculation so perfectly. You are an inspiration, mate.
Thanks, Tony! That's a big compliment. Cheers!
First comment! Your videos are very helpful and interesting. This channel is the first for me to click the bell button. Keep up the great work!
Thanks so much! Really appreciate that. Cheers!
Incredibly well explained and clear, thank you so much! Great efficient direct communicator, just subscribed and liked 👌
Now you've got Philip Bloom just casually dropping your next intro 😂
😃🤓
I love your explanation videos! It really helped me in making a camera buying decision (now just need to save up). I can't wait to see more content like this. You are AWESOME!!!
Thanks so much! Glad you enjoy it. Cheers!
That was a epic presentation of the T and F. You're like the professor of video/photo. Thank you for Undoing it.
Thanks a bunch! My pleasure.
I had that question for a while now in my head and you answered it beautifully! Thank you 🙏😍
Awesome! Thanks for saying so.
Old school guy, and old too! Never occurred to me before, use my gear for mostly documenting art work etc., kinda clinical in a way, because my modern gear allows so many interesting things to to in regards to other avenues, why not, very well explained, Thanks!
Cheers! Thanks for sharing.
No, Thanks you, the ability to explain to others without the use of crayons is no simple feat, the math is easy, I hope, but too encourage others out of the blue, rare, hope you teach others,
Great, short but prizisely explained. Thx a lot, now self I got it.
Glad to hear it. Thank you.
My god, this episode had a transmittance value of 100%
T-stop that!🖤🖤
Haha. Puns! Thanks. 😃
A very useful information,all photographers shd know about this.Thanx.
I miss the old “what is HAPpening”
Great video as always!
Thanks Gerald, great video, very clear. Thank you very much, I was recently wondering how T and F stops differed...
Thanks, Julien! Appreciate that.
I think my head just exploded! Man you are smart! I went from thinking it would be cool to hang out, to now thinking that I would be reticent to open my mouth ;) Kidding aside, great stuff as usual Gerald. Hey here's how you can lighten it up. "I'm Gerald undone and I'm not wearing pants"
Haha! Thanks, Robert. Hilarious comment and I'm definitely using that greeting.
As I know you want to be original, full transparency. Chevy Chase used it first on SNL
I'm Chevy Chase... and you're not.
Thank you doctor. I feel much better.
M y teacher was a Eygyptologist, thanks for putting your skills to good use!
Excellent explanation - thank you!
Gerald, could you start with "A 50 is a 50 is 50 no matter what."
Also, make a video about it if it isn't. :D
You are Wikipedia of sensors and optics. I love your videos because they are straight to the point and simple to follow and always learn something out of it.
Just a small suggestion for this video though to make it consistent with notations you've used.
At 0:36 f/N=D where f = focal length, N = f-number and D = Diameter of entrance pupil.
But at 1:40 T=f/N/sqrt(trans%) where I understand that you meant f-stop (e.g. f/2.8) by f/N but I got confused as you already used f for focal length before. I initially thought you meant D by f/N. Maybe you could write T=N/sqrt(trans%) or T=f/D/sqrt(trans%) to be consistent.
I know what you mean, but D needs to be measured in mm, where f-stop is a ratio. So in f/n, f still is focal length, but it's only the N that really matters. I suppose N from earlier would have been better. I was just trying to express it as it's written f/2.8, etc. But I think you know what I mean.
Glad you're diggin' the videos. Appreciate the comment.
@@geraldundone Thanks! I see what you mean.
Spot on, faster than I can google it and understand it ;)
Glad it was helpful. Thanks!
Great video - thanks a lot for being so comprehensive like always!
This was waaaaay to early for me to watch this video, but I'm sure it is great as usual 👍
😂👍
INTERESTING. Super informative vid, thanks man!
Cheers! Thanks, Jackson.
Great work as always Gerald !!! I would love to see you tackle SS in video and going above or below the 180 degree rule
Thanks for the suggestion and kind words.
Lol you should start your next video with “Hold onto your butts....” 😂😂👍🏽
Excellent video. Very well explained.
great explanation, I do enjoy this videos you produce. Thank you.
Thanks, John!
Cheers Gerald. Nailed it 👌
Nicely explained. Even through a single pane of optically clear glass, less than 100% of the incident light is transmitted. At least 4% is lost to reflection. Can you imagine what happens in a zoom lens with 14 or 15 elements, coatings and all?
I'm always impressed when they manage to do a zoom lens that doesn't lose too much.
I love this channel! Thanks for the constant knowledge bombs!
Thank you for the kind words!
Fantastic explanation!
Very good explanation
Thank you! 😃
Some older macro lenses don't have constant transmission at a given f-stop. They require positive compensation the closer the camera is to the subject.
I like this video and I agree the the f and t stop shouldn't be seen as adversarial, but, manufactures should put both f and t stop 'on the can'. I do want to know which prime is going to give me a brighter image because I shoot photo and video, it also can give a clue to which lens has better micro contrast and will help me bring up the shadows with less noise and easier. I actually consider this as part of my purchase, especially in a system that has a gluttony of lenses to choose from like MFT.
I agree with you, but I wonder if we'd have to pay a premium for that.
i liked it so much i clicked like twice
The best explanation of t and f on youtube! thanks. Do you have plans to do a video regarding AF systems? what is the main difference and which one is better for video?
Thanks so much! I made that video already. 😃 Here's the link: th-cam.com/video/yaJFOH_gmGM/w-d-xo.html
Nice explanation. It's concise and no more complicated than it needs to be. Have you, or anyone else for that matter, seen any tables of light transmission values of common or popular stills lenses? With more videographers using DSLR and mirrorless cameras, and the standard stills lenses that come with them, I'd think a table like that would be useful.
thanks,
richard hargrove
--
“Everything that needs to be said has already been said. But since no one was listening, everything must be said again.”
- André Gide
It would be nice to have a simplified resource for that. DxOMark measures it for the lenses they test, but there are a lot of lenses that aren't covered.
Hello... in astronomy we talk about light in terms of diameter of the mirror... so 6 inches, 8 inches... because we are all about gathering light from the night sky.
Why is this not possible in photography?
Wouldn't a larger diameter lens take in more light than a smaller lens?
I've seen the tiniest of pancake lens... with the largest of apertures... how can they be good at taking in light?
Thanks for the opportunity to vent here!
Your video is very informative!
very useful as always (:
Hi,
finally an explaination. What not clear is this: Sony web site, two lenses: about the first just says f/1.4; the second f/2.8 T/5.6 (if I recall the values). So why does Sony declare the T value only for the second one? How am I supposed to find out the T for the first?
Regards.
Gerald! Thank you! Thank you! Thank you!
Cheers!
Wow, well done! I did learn something thank you....
Great! Glad to hear it.
nice this is a better explanation of this
dude youre incredible
Thanks for another winner!!!
😃👍🙏
Thank you for the info very helpful 😍
What would be a practical-ish way to get the transmission data for fstop lenses? Nothing laboratory exact, but say I know the transmission data for a specific lens I have, and I want to figure out the transmission data for a vintage lens. How do I go about calculating the transmission by comparing shots from both lenses in a controlled lighting situation to get a really rough estimate of where the transmission for that lens might be, give or take a few percent.
Again learned something new
Awesome! Thanks for commenting.
If one is looking for a fast lens, lets say thinking of purchasing a f1.4 factor lens then it would be helpful to know the T stop when comparing lenses, wanting the "fastest" lens. So what is faster, the Canon 50 1.4, Sigma 50 1.4, Tamron 50 1.4, etc.
So... Is there some third party or photo club, etc, that has measured the max T-stop of common photography lenses? (I'm amazed at what clubs and interest groups have done in other cases, and this seems useful.)
Intro “im Gerald Undone and what up everybody, welcome back to another video” (Peter style) 😉
Haha. This one would cause a stir in the comments.
I have no idea in about 80% of what you said in that video. 😄😄 However, if I focus I will eventually get the hang of it. In the meantime...What is the equivalent of t2.2 in f stop? Thanks much.
So knowing the T-stop would be more useful in knowing which lens would perform better in low light?
Hi Gerald! How do we measure the light transmittance?
On a zoom lens, is the T-stop pretty much fixed throughout the zoom range or is it changing? It seems like the T-stop should be pretty much fixed as the light needs to go through the same number of elements regardless of the chosen focal length.....
Is there a website you know of that compares T-stops of various lenses used in photography? Thanks!
so higher T-stop is generally better? more accurate color/sharpness?
Do you have any videos on exposure values?
Gerarldpedia Math Edition...
Is the transmittance score usually available information for most lenses?
Great video. Question: If one needed to convert from t-stops to f-stops on a cinema lens to calculate the depth of field, where would you find information on the "transmittance percentage" of a lens? I've been looking and can't seem to find any information on this. Is it called something else? Is converting from t to f using the equation you mentioned required or could you just estimate by rounding down to the nearest f-stop (as you also mentioned)? Is there a different way of calculating depth of field with just the t-stop and without needing to convert to f-stops?
I just bought my first cinema lens, which is a Rokinon 85mm. I usually use a light meter to check my exposure but I don't know how to convert the f stop to the T stop. Help.
Thankute teacher!
great info... hey now I'm curious , I have a Mitakon-Zhongyi 35mm f/0.95 II speedmaster lens for Sony E-mount.... would you be able to tell me what the T-stop for that lens would be ?
I can't tell you, no. It would have to be tested.
Great video, as always!
Thanks, Lukas!
Mitakon 50 f/0.95 lens is near T1.4 at wide open. So, this lens has surprisingly low light transmission value compared to f-stop. I heard E-mount has small mount diameter that cause light loss. This would be the reason why Nikon Z and Canon EF/RF mount has bigger mount diameter.
That is a surprisingly loss, yeah. Thanks for sharing.
Isn't there also a kind of maximum transition or sensitivity by the sensor - and how would they relate? Does either lens or sensor limit the t-stop by it's own capabilitiy or is one relevant for the other?
Well sensors can always receive more light until they're clipped. So if you have a high enough shutter speed you should be able to keep increasing the T-stop. There are design limitations though that can occur based on mount size and flange shape where transmission goes down because of the body.
I recall it was something about the photodiodes on the sensors themselves, someone claiming that they would limit the light transmission no matter what wide aperture lens you would use.
Why is the square root here? Any demonstration would be great
Genius!
how do we figure out the transmission efficiency?
I had a question that I can't find the answer to: I use the Sony a7iii and when I change the aperture in photo mode, I can hear a slight bit of noise from the aperture blades moving. If I then put it into video mode there is absolutely no noise when changing the aperture. This happens across multiple lenses and it just has me curious as to why, if Sony has the capability to make the aperture silent in video, it doesn't do so for photos? Other people have suggested the auto focus is the cause but it happens when auto focus is turned off.
Hmm... I'll look into that.
Gerald, have you ever tried a gentle oil to put in your hair to keep the flyaways at bay? I use pure vitamin E oil and it feels wonderful in my equal-length hair.
I have a cream, but I typically don't like to put much in my hair. Going for a natural look. The flyaways were a bit rambunctious today though.
@@geraldundone Hahaha, it's that 4k super sharp video that helped those flyaways get noticed.
On a bad hair day - film with a potato (or downscale to minecraft resolution).
Finally the biggest mystery has been solved. I mean I am really clumsy to search t vs f over Google.
So exemple, T 1.9 vs F 1.4 Wich one have more bike more light come through?
There's no way of knowing without measuring. That's his whole point.
Although at f1.4 it would have to have terrible light transmittance to not beat T1.9. It's probably T1.6 or so.
Will you be able to do a review of the Panasonic LUMIX S1 ?
I'm planning on it, yeah, but still waiting to get my hands on one.
@@geraldundone Still sucks that you have to pay for a firmware update to unlock their logs.
Man you make me feel like I know nothing lol.
If in my photometer I have F-stops and my lens has T-Stops, what is the equivalence between T and F approximately? sorry for my english :(
So on lenses that only carry T stops, how would you calculate DOF?
You can't really. You need to find or at least estimate the nearest f-stop.
If I ever get to direct a film I’m hoping that I have some dude like this on set lmfao
Wow!
my brain is making a frying egg noise but i’ll get it after watching three more times
Cool
0:15 now i feel stupid that i'm "watching" podcast in 4k :(
😂😃