Great explanation overall. The insight into the sharpness of the central area of the lens is particularly valuable. It's important to clarify that "full frame" isn't actually "full"; it's a crop from medium format. Medium format (digital) is itself a crop from medium format (film). Additionally, there are even larger formats like 4x5" or 5x7" film, which capture incredible detail if the lens can deliver it. Therefore, choosing full frame doesn't necessarily mean you're opting for the "fullest" or "best" option. There's always some sacrifice. Crop sensor cameras (APS-C, DX) often offer the best value for the price. Micro 4/3 and full frame cameras, in contrast, tend to be more specialized and come at a higher cost. Regarding dynamic range and color depth, the differences between modern cameras, whether full frame or crop, are minimal. These factors have been extensively measured and verified on platforms like DPReview. DOF and low-light performance - FF is clearly a winner. Full frame typically exhibits better noise performance, often by at least one stop, compared to crop sensors. Indirectly, there's also the consideration of lens quality and availability. It's generally more challenging to manufacture wide-angle lenses with equivalent sharpness, minimal color fringing, and distortion compared to full frame counterparts for the same price. Good example is Canon's 35mm/2 vs Canon 50mm/1.4 which is half the price. So on crop you end up with 56mm and equivalent DOF of f/3.2 for twice as much as you pay for 50mm f/1.4 on FF. In this regard, FF is unbeatable.
Hi Forest, this is a well done video. However, I found the side-by-side photos of DOF at the end confusing. Only after I rewound the video and watched again did I see the previous captions on the 2 images. When you show each photo individually, for the 80mm on the crop sensor you include the 120mm Equivalent focal length in the caption. This helps explain both the field of view and the background blur difference compared to the 135mm (actual focal length) shown in the full frame picture. Consider changing the caption in the side-by-side comparison to include the 120mm EFL. The part about different DOF always twists my brain! 🙂 Thanks!
Thank you Kathy! Great point. We could have made that more clear. Unfortunately it's too late now (no way to adjust after upload unfortunately). It's so true that the whole "shallower DOF on full frame" is a mind melter. Haha. It's a tough one to explain.
On one hand you say focal length is what it is and on the other mention free longer focal length using a crop sensor. You only get “free” focal length when you compare prints at the same enlarged size, I.e. 8x10. Natively, an APS-C sensor makes a smaller image than Full Frame at the same print resolution, say 300dpi. That is why a crop sensor lens’ focal length is often referred to as a 35mm equivalent.
Get more from your lens and buy full frame. Most of them have APSC mode so thats like having 2 lenses. And now with Panasonic's hybrid zoom, it could be more. Lenses are EXPENSIVE. So save some by going full frame.
Hey Forest, well done, but I think you missed an important factor in the comparison ... the factor that actually led me to choose a full-frame camera myself. That factor is resolution. Any lens is only going to resolve so well -- I've usually seen it measured as lines of resolution at a given distance. And the number of lines resolved across the field of view (the real light circle you described, not the sensor area) is a fixed quantity no matter what sensor you put behind it. So from this reality, the number of lines of resolution that go into your finished image is reduced proportional to any crop that happens. Whether this matters, of course, depends on how those lines get distributed across however many pixels the sensor serves up. If the lens can resolve more lines than your pixel density, then you're not gonna notice a bit of difference with the crop. But for an example, the Canon 6d (which I shoot) and 7d mk ii (equivalent crop sensor) are 20mp cameras. Using the same lens on both, there will be more pixels per line on the 6d. In my experience, this has led to much sharper landscape photos on the full-frame camera. Now, as you so correctly pointed out, I've already tipped my hand in that high-rez landscape photos are one of my objectives (also means the higher dynamic range is desirable, but you already said that). As I'm also a wildlife photographer, I'd actually buy one of each if I could afford it ... but as a guy with a day job who makes exactly $0 off of his photography, I don't have that budget. Hence, for me, the full-frame camera and manually cropping when I shoot animals and birds has been the best choice. Still, great information!
True! Resolution does play an important role. In astrophotography we would call this over/under sampling. Unless I'm thinking about it backwards (I could be), I do believe that your 7D Mark II would result in more pixels per line than your 6D as the pixel size of that camera is smaller. With that said, I'm surprised that you are getting sharper images with your full frame camera as I would expect the opposite.
@@forestchaput I think maybe you do have it backwards. If the sensor-to-lens combo is such that your dealing with more than maybe two to three (I'm guessing) pixels per line, you're "wasting" pixels, because all the pixels in the world can't resolve beyond the sharpness of the lens. On the other hand, if you have more than a couple lines per pixel, your sensor is "wasting" lens resolution (lines), because it can't capture the full detail which the lens is delivering. Now to the specifics: taking a look at a couple of my sharpest images taken with the 6d: a landscape taken with the Canon 24-105 f/4L and a bird taken with the Tamron 150-600 f/5-6.3 G2, it appears to me that if anything, my 6d is wasting lines and I could use more pixels if I had 'em. Which may mean that if I had a 7d mk ii (I don't), I might have gotten a sharper image of the bird. But of course I would have lost image breadth on the landscape, for the very vignetting issue you describe in your video (5d mk iv on the wishlist LOL). With a lesser lens, however, the story becomes different. Looking at a couple images of birds I shot with the Tamron 70-300 f/5.6 Di VC, which is a softer lens, it looks like my sensor was probably getting close to the maximum resolution of the lens and a higher pixel density probably wouldn't have achieved anything. Functionally, I'm guessing this might also have an effect on depth of field in low light ... in that the larger light capture area of the full-frame sensor would not require the maximum aperture as quickly. But that's another question. Ideally, of course, my theory would be put to test with a good high-resolution target and both full-frame and APS-C sensor cameras. Lacking the necessary equipment, I can only theorize.
Thanks for the great video, Forest. I know you do astrophotography as well. Any thoughts on crop vs. full frame dedicated astrophotography cameras (assuming the optics of a telescope can support a full frame)? I currently use ZWO ASI2600 MC and MM cameras but often think about using a full frame dedicated camera. Just curious what you think. Thanks again for the information and excellent explanations!
You are welcome! Great question. If your scope can handle it, there is little reason not to go with a full frame camera as you can maximize the abilities of your scope (and have to do mosaics less often). Personally, I use the 6200MM Pro as my scope can evenly illuminate that sensor.
Thanks a lot for another great APS=C vs FF video. I believe that the comments on depth of fielf (DOF) don't agree very much with DOF calculators, geometry, and easy to verify practical experiences. The determining factor for the DOF at a given focusing distance is the product of the diameter of the aperture by the focal length. You can easily check on photo pills or DOFMaster for instance. With an aperture diameter of 50mm and a focal length of 50mm (f1.0), the DOF is the same as with an aperture diameter of 25mm and a focal length of 100mm (f4.0) (at the same focusing distance obviously). Pushing it a bit further, at a given angle of view and given aperture diameter, an APS-C lens on an APS-C camera will produce images indistinguishable from a FF lens on a FF camera. For instance, a scene shot with a 25mm f/2.0 lens on an APS-C camera (canon) will have the same DOF and field of view as a FF 40mm f/3.2. If you push the experience that far, you can press the shutter as well. Do it with the same shutter speed (using auto-ISO) and ask someone else if they can figure out which picture was shot with the crop sensor, without looking at the metadata (even with pixel peeping and analysis of noise and dynamic range).
I have all Full Frame lenses, and I have 2 Full Frame sensor camera bodies and 1 DX camera body. no complaints yet! I use them exactly as described in the video!!
Great explanation overall. The insight into the sharpness of the central area of the lens is particularly valuable. It's important to clarify that "full frame" isn't actually "full"; it's a crop from medium format. Medium format (digital) is itself a crop from medium format (film). Additionally, there are even larger formats like 4x5" or 5x7" film, which capture incredible detail if the lens can deliver it. Therefore, choosing full frame doesn't necessarily mean you're opting for the "fullest" or "best" option. There's always some sacrifice.
Crop sensor cameras (APS-C, DX) often offer the best value for the price. Micro 4/3 and full frame cameras, in contrast, tend to be more specialized and come at a higher cost.
Regarding dynamic range and color depth, the differences between modern cameras, whether full frame or crop, are minimal. These factors have been extensively measured and verified on platforms like DPReview. DOF and low-light performance - FF is clearly a winner. Full frame typically exhibits better noise performance, often by at least one stop, compared to crop sensors.
Indirectly, there's also the consideration of lens quality and availability. It's generally more challenging to manufacture wide-angle lenses with equivalent sharpness, minimal color fringing, and distortion compared to full frame counterparts for the same price.
Good example is Canon's 35mm/2 vs Canon 50mm/1.4 which is half the price. So on crop you end up with 56mm and equivalent DOF of f/3.2 for twice as much as you pay for 50mm f/1.4 on FF. In this regard, FF is unbeatable.
We appreciate your insights!
Hi Forest, this is a well done video. However, I found the side-by-side photos of DOF at the end confusing. Only after I rewound the video and watched again did I see the previous captions on the 2 images. When you show each photo individually, for the 80mm on the crop sensor you include the 120mm Equivalent focal length in the caption. This helps explain both the field of view and the background blur difference compared to the 135mm (actual focal length) shown in the full frame picture. Consider changing the caption in the side-by-side comparison to include the 120mm EFL. The part about different DOF always twists my brain! 🙂 Thanks!
Thank you Kathy! Great point. We could have made that more clear. Unfortunately it's too late now (no way to adjust after upload unfortunately).
It's so true that the whole "shallower DOF on full frame" is a mind melter. Haha. It's a tough one to explain.
On one hand you say focal length is what it is and on the other mention free longer focal length using a crop sensor. You only get “free” focal length when you compare prints at the same enlarged size, I.e. 8x10. Natively, an APS-C sensor makes a smaller image than Full Frame at the same print resolution, say 300dpi. That is why a crop sensor lens’ focal length is often referred to as a 35mm equivalent.
Good insight!
This is amazing, for someone like me who wants to learn more and effectively differentiate what I need vs what reviewers want you to believe.
I’m glad you liked it!
Get more from your lens and buy full frame. Most of them have APSC mode so thats like having 2 lenses. And now with Panasonic's hybrid zoom, it could be more. Lenses are EXPENSIVE. So save some by going full frame.
I agree (if you value image quality and DOF above a smaller camera system)!
🙏
🎉
I still don't which one to get 😂. This vide is helpful Thank you
Hey Forest, well done, but I think you missed an important factor in the comparison ... the factor that actually led me to choose a full-frame camera myself. That factor is resolution. Any lens is only going to resolve so well -- I've usually seen it measured as lines of resolution at a given distance. And the number of lines resolved across the field of view (the real light circle you described, not the sensor area) is a fixed quantity no matter what sensor you put behind it. So from this reality, the number of lines of resolution that go into your finished image is reduced proportional to any crop that happens.
Whether this matters, of course, depends on how those lines get distributed across however many pixels the sensor serves up. If the lens can resolve more lines than your pixel density, then you're not gonna notice a bit of difference with the crop. But for an example, the Canon 6d (which I shoot) and 7d mk ii (equivalent crop sensor) are 20mp cameras. Using the same lens on both, there will be more pixels per line on the 6d. In my experience, this has led to much sharper landscape photos on the full-frame camera.
Now, as you so correctly pointed out, I've already tipped my hand in that high-rez landscape photos are one of my objectives (also means the higher dynamic range is desirable, but you already said that). As I'm also a wildlife photographer, I'd actually buy one of each if I could afford it ... but as a guy with a day job who makes exactly $0 off of his photography, I don't have that budget. Hence, for me, the full-frame camera and manually cropping when I shoot animals and birds has been the best choice.
Still, great information!
True! Resolution does play an important role. In astrophotography we would call this over/under sampling.
Unless I'm thinking about it backwards (I could be), I do believe that your 7D Mark II would result in more pixels per line than your 6D as the pixel size of that camera is smaller.
With that said, I'm surprised that you are getting sharper images with your full frame camera as I would expect the opposite.
@@forestchaput I think maybe you do have it backwards. If the sensor-to-lens combo is such that your dealing with more than maybe two to three (I'm guessing) pixels per line, you're "wasting" pixels, because all the pixels in the world can't resolve beyond the sharpness of the lens. On the other hand, if you have more than a couple lines per pixel, your sensor is "wasting" lens resolution (lines), because it can't capture the full detail which the lens is delivering.
Now to the specifics: taking a look at a couple of my sharpest images taken with the 6d: a landscape taken with the Canon 24-105 f/4L and a bird taken with the Tamron 150-600 f/5-6.3 G2, it appears to me that if anything, my 6d is wasting lines and I could use more pixels if I had 'em. Which may mean that if I had a 7d mk ii (I don't), I might have gotten a sharper image of the bird. But of course I would have lost image breadth on the landscape, for the very vignetting issue you describe in your video (5d mk iv on the wishlist LOL).
With a lesser lens, however, the story becomes different. Looking at a couple images of birds I shot with the Tamron 70-300 f/5.6 Di VC, which is a softer lens, it looks like my sensor was probably getting close to the maximum resolution of the lens and a higher pixel density probably wouldn't have achieved anything.
Functionally, I'm guessing this might also have an effect on depth of field in low light ... in that the larger light capture area of the full-frame sensor would not require the maximum aperture as quickly. But that's another question.
Ideally, of course, my theory would be put to test with a good high-resolution target and both full-frame and APS-C sensor cameras. Lacking the necessary equipment, I can only theorize.
Thanks! This was great.
Thanks for the great video, Forest. I know you do astrophotography as well. Any thoughts on crop vs. full frame dedicated astrophotography cameras (assuming the optics of a telescope can support a full frame)? I currently use ZWO ASI2600 MC and MM cameras but often think about using a full frame dedicated camera. Just curious what you think. Thanks again for the information and excellent explanations!
You are welcome! Great question. If your scope can handle it, there is little reason not to go with a full frame camera as you can maximize the abilities of your scope (and have to do mosaics less often). Personally, I use the 6200MM Pro as my scope can evenly illuminate that sensor.
Thanks a lot for another great APS=C vs FF video. I believe that the comments on depth of fielf (DOF) don't agree very much with DOF calculators, geometry, and easy to verify practical experiences. The determining factor for the DOF at a given focusing distance is the product of the diameter of the aperture by the focal length. You can easily check on photo pills or DOFMaster for instance. With an aperture diameter of 50mm and a focal length of 50mm (f1.0), the DOF is the same as with an aperture diameter of 25mm and a focal length of 100mm (f4.0) (at the same focusing distance obviously). Pushing it a bit further, at a given angle of view and given aperture diameter, an APS-C lens on an APS-C camera will produce images indistinguishable from a FF lens on a FF camera. For instance, a scene shot with a 25mm f/2.0 lens on an APS-C camera (canon) will have the same DOF and field of view as a FF 40mm f/3.2. If you push the experience that far, you can press the shutter as well. Do it with the same shutter speed (using auto-ISO) and ask someone else if they can figure out which picture was shot with the crop sensor, without looking at the metadata (even with pixel peeping and analysis of noise and dynamic range).
Thanks for your input!
I have all Full Frame lenses, and I have 2 Full Frame sensor camera bodies and 1 DX camera body. no complaints yet! I use them exactly as described in the video!!
Nice!