Optical Limits reviews Canon RF 15-35mm f/2.8 USM L IS

SteveC

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Thanks for sharing (y) yup, the vignetting is ridiculous for lens at this price point, no two ways about it...

I have tried it and it wasn’t as crazy as I expected, but I shot in a well lit store and at low iso so the files turned out okay. But any higher than 200 iso and this is a dealbreaker for me. Such a shame really...

We are likely going to see more and more lenses that rely on the EVF to mask optical imperfections, since the camera will do the same thing. This is something new to an all-electronic (no optical viewfinder) camera; it could not have been done before.
 
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We are likely going to see more and more lenses that rely on the EVF to mask optical imperfections, since the camera will do the same thing. This is something new to an all-electronic (no optical viewfinder) camera; it could not have been done before.
And the cameras are going to cook the 'RAW' files so you can't ever not see the lens aberrations, Canon already do it with the P&S's and Nikon do it with the Z's, I'm sure they aren't alone.
 
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SteveC

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And the cameras are going to cook the 'RAW' files so you can't ever not see the lens aberrations, Canon already do it with the P&S's and Nikon do it with the Z's, I'm sure they aren't alone.

And you know, I can live with that for lower-tier cameras. Part of the price you pay for economy is lower intrinsic quality.

But now there's the RF 24-240 that couldn't be released without a firmware upgrade first...because it has horrific vignetting and barrel distortion at the shorter end, and so the camera had to be trained to hide it. If that were the alternative I had (and no, it isn't; plenty of others) I'd keep my 18-200 Tamron for the EF-M, which I'm pretty confident doesn't resort to such monkeyshines (why would Canon help Tamron sell lenses?). Yes, its crop frame which makes the job easier (barrel distortion gets worse as the projected image gets wider), but I doubt such distortion could be hidden even in a crop size. (And it's even an 11+:1 zoom versus 10:1.)
 
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And you know, I can live with that for lower-tier cameras. Part of the price you pay for economy is lower intrinsic quality.

But now there's the RF 24-240 that couldn't be released without a firmware upgrade first...because it has horrific vignetting and barrel distortion at the shorter end, and so the camera had to be trained to hide it. If that were the alternative I had (and no, it isn't; plenty of others) I'd keep my 18-200 Tamron for the EF-M, which I'm pretty confident doesn't resort to such monkeyshines (why would Canon help Tamron sell lenses?). Yes, its crop frame which makes the job easier (barrel distortion gets worse as the projected image gets wider), but I doubt such distortion could be hidden even in a crop size. (And it's even an 11+:1 zoom versus 10:1.)
Well RAW cooking is going to come more and more prevalent, unfortunately. A sure benefit of MILC's, and progress..... ;)
 
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Well RAW cooking is going to come more and more prevalent, unfortunately. A sure benefit of MILC's, and progress..... ;)

If the end file looks good, I don't think I am going to mind. And as long as the end result is still real, multiple exposures to make a cleaner picture are a-ok with me(like a phone), but I draw the line when it is trying to digitally make the out of focus area smoother than the lens can produce so that it looks like a better lens.
 
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koenkooi

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If the end file looks good, I don't think I am going to mind. And as long as the end result is still real, multiple exposures to make a cleaner picture are a-ok with me(like a phone), but I draw the line when it is trying to digitally make the out of focus area smoother than the lens can produce so that it looks like a better lens.

I'd still like the RAW to be, well, RAW and have DPP/LR/C1/etc do the cooking.
 
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And the cameras are going to cook the 'RAW' files so you can't ever not see the lens aberrations, Canon already do it with the P&S's and Nikon do it with the Z's, I'm sure they aren't alone.

A camera can cook back the 4.5 stops of light fall off in the corners so one can't ever see it?
 
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A camera can cook back the 4.5 stops of light fall off in the corners so one can't ever see it?
Yes it can, it can do it to any camera in playback mode but if your camera has an EVF it can do it in the 'viewfinder' live feed too. Now many might say 'so what?' and most of the time I could agree, but if you are chasing the highest IQ you can then having the corners of your image already lifted 4 stops to 'correct' for the lens really starts to limit the artistic choices you have with that file. Personally one of the things I have liked about Canon has been their comparatively unfettered RAW files, I believe MILC's and the keen competition in the sector are going to force this kind of jiggery pokery onto all the manufacturers.
 
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Yes it can, it can do it to any camera in playback mode but if your camera has an EVF it can do it in the 'viewfinder' live feed too.

I was referring to how it would look on a computer screen or printed, rather than EVF or the camera's screen.

if you are chasing the highest IQ you can then having the corners of your image already lifted 4 stops to 'correct' for the lens really starts to limit the artistic choices you have with that file.

Exactly. If the sensor has 10 stops of dynamic range, and the lens has ~4 stops of vignetting at the corners, that will leave 6 stops of dynamic range in the corners, and cooking in the camera can't add two more.
 
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I was referring to how it would look on a computer screen or printed, rather than EVF or the camera's screen.

It will look on a computer screen as it would look in the EVF or back screen on review, it is baked into the RAW file so you can't undo it even third party programs like Lightroom etc won't be able to 'undo' the bake.
 
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Del Paso

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I can understand why heavy vignetting can be (is) an issue for many of us.
Less for me, since I'd be using an ultrawide almost exclusively at F.8 or less, and at low ISO, for landscape photography.
Yet, I still dislike manufacturers relying more and more often on software to "correct" optical defects, like vignette, distorsion, c.a. etc...
So, for now, I'll keep using my 16-35 F4 and EF 14 F2,8.
 
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SecureGSM

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My EF 16-35/F2.8 III L with around 5 stops of vignetting in extreme corners isn't much better. Sony E 16-35/F2.8 GM is a much better vignetting controlled lens of course. I was thinking Sigma 14-24/F2.8 at some stage but there are issues as well: a softness at 24mm end, CA levels and pronounced focus shift

 
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It will look on a computer screen as it would look in the EVF or back screen on review, it is baked into the RAW file so you can't undo it even third party programs like Lightroom etc won't be able to 'undo' the bake.

A back screen's resolution is ~3" diagonal and ~150K pixel, making it much easier to hide aberrations.
 
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Quirkz

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And you know, I can live with that for lower-tier cameras. Part of the price you pay for economy is lower intrinsic quality.

But now there's the RF 24-240 that couldn't be released without a firmware upgrade first...because it has horrific vignetting and barrel distortion at the shorter end, and so the camera had to be trained to hide it. If that were the alternative I had (and no, it isn't; plenty of others) I'd keep my 18-200 Tamron for the EF-M, which I'm pretty confident doesn't resort to such monkeyshines (why would Canon help Tamron sell lenses?). Yes, its crop frame which makes the job easier (barrel distortion gets worse as the projected image gets wider), but I doubt such distortion could be hidden even in a crop size. (And it's even an 11+:1 zoom versus 10:1.)

Despite the rf24-240 requiring in camera correction at the wide end, it’s still an excellent lens. Reasonable compromises vs great portability/range.

There’s a lot of clickbait hate on the optical correction out there, but there are also more in depth reviews. Plus it’s wider than the tampon 18-200, 24 vs 28mm equivalent, which I prefer.

Is it great? No. But it’s pretty damn good, and the wide angle distortion is less of an issue than people make it out to be.
 
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AlanF

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It's pretty well inevitable with a short sensor-rear element distance that you will get heavy vignetting. The light from, for example, the extreme right of the rear element strikes the extreme left of the sensor at a very sharp angle. So you have to correct for it either electronically or physically. A flexible concave sensor would be one answer, but I think that would be rather too esoteric. These problems don't worry me as I mainly use telephotos and these have the rear elements well inside the lens. My Sony RX10IV gives excellent images despite heavy corrections for distortion and vignetting.
 
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