RF 15-35mm F2.8 Image Quality samples up @ The Digital Picture

Viggo

EOS 5D SR
Dec 13, 2010
4,172
734
Is it worse because the R uses less sharpening or is it just worse than the 16-35 f4 L IS? Seems like more vignetting also. Not what I expected really.. Seems like it's very little distortion, but even at f4 it seems worse than the 16-35 f4 L IS. And only the mid frame seems marginally better than the RF50 at f1.2, off center the RF50 looks better. The RF50 is very sharp wide open, and the 15-35 seems close, so it's not unsharp. I really don't know, lol.
 

Ramage

EOS M50
Aug 27, 2019
28
21
Is it worse because the R uses less sharpening or is it just worse than the 16-35 f4 L IS? Seems like more vignetting also. Not what I expected really.. Seems like it's very little distortion, but even at f4 it seems worse than the 16-35 f4 L IS. And only the mid frame seems marginally better than the RF50 at f1.2, off center the RF50 looks better. The RF50 is very sharp wide open, and the 15-35 seems close, so it's not unsharp. I really don't know, lol.
I was looking at the 16-35 F4 in comparison, I wonder if the 5Ds R high resolution is what is making the difference.
 

LesC

EOS RP
Jun 27, 2013
247
52
Essex, UK
500px.com
Seems rather odd that it looks so apparently poor. Wonder if this could be a pre-production model or a dodgy copy? Either way I guess we'll need to wait for further reviews & user findings once it's on general sale.

I do wonder about these comparisons though - if you compare the RF24-105 F4L on an EOS R to the EF24-70 F2.8L MKII on the same body, the charts suggest the RF lens is better at both 24 & 70 ends in the corners at least ?? Something doesn't seem right here ...
 
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Viggo

EOS 5D SR
Dec 13, 2010
4,172
734
Seems rather odd that it looks so apparently poor. Wonder if this could be a pre-production model or a dodgy copy? Either way I guess we'll need to wait for further reviews & user findings once it's on general sale.
I suspect it has something to do that default sharpening with R is lower, I’ll try and find a quote (y)
 
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Ramage

EOS M50
Aug 27, 2019
28
21
If this is the sharpness we can expect from the 15-35 I will be disappointed, I just compared the RF 24-105 and the 24-105 looks sharper @f4 in every focal length that I tried.

I have the 15-35 on pre-order so I am hoping something is wrong with the results.

Hard to pay $3300 Canadian for a lens that is less sharp than my $1100 16-35 F4
 
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jd7

EOS 7D MK II
Feb 3, 2013
732
100
Seems rather odd that it looks so apparently poor. Wonder if this could be a pre-production model or a dodgy copy? Either way I guess we'll need to wait for further reviews & user findings once it's on general sale.

I do wonder about these comparisons though - if you compare the RF24-105 F4L on an EOS R to the EF24-70 F2.8L MKII on the same body, the charts suggest the RF lens is better at both 24 & 70 ends in the corners at least ?? Something doesn't seem right here ...
Perhaps, although I'm sure I've read the shorter flange distance often used by mirrorless cameras (including Canon's RF mount) makes UWA more challenging to design. Maybe we are seeing evidence that the RF mount (and other short flange distance mounts) have disadvantages as well as advantages? (This may not be the answer - and I'm certainly no lens designer - but I'll be interested to find out more information though when more people have had a chance to test the 15-35.)
 

Act444

EOS 6D MK II
May 4, 2011
993
102
Wow, a bit underwhelming to be honest but need more takes/reviews to be sure.

Let's not forget that with the EF version it took them 3 iterations to "get it right" - the first 2 versions were quite meh as well, as was the 17-40. Maybe the RF design poses new challenges in this realm..? Would one get better results adapting the EF 2.8 III instead? I'd like to see that comparison.
 
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Ramage

EOS M50
Aug 27, 2019
28
21
I wonder if the R used to capture these images had 1.4 firmware install. I expect the new firmware will include support for the 15-35 and the 24-70 and that might make a difference.

Another week and we should start to see reviews.
 

Viggo

EOS 5D SR
Dec 13, 2010
4,172
734
Perhaps, although I'm sure I've read the shorter flange distance often used by mirrorless cameras (including Canon's RF mount) makes UWA more challenging to design. Maybe we are seeing evidence that the RF mount (and other short flange distance mounts) have disadvantages as well as advantages? (This may not be the answer - and I'm certainly no lens designer - but I'll be interested to find out more information though when more people have had a chance to test the 15-35.)
Not more challenging, but easier, it’s for longer FL’s that the short flange distance doesn’t matter much.
 

Viggo

EOS 5D SR
Dec 13, 2010
4,172
734
Wow, a bit underwhelming to be honest but need more takes/reviews to be sure.

Let's not forget that with the EF version it took them 3 iterations to "get it right" - the first 2 versions were quite meh as well, as was the 17-40. Maybe the RF design poses new challenges in this realm..? Would one get better results adapting the EF 2.8 III instead? I'd like to see that comparison.
Do you think people have any kind of patience to wait three generations for a decent uwa for RF? No, this is it for the next 10-12 years at least, and it has to be at least matching the 16-35 L III.
 

jd7

EOS 7D MK II
Feb 3, 2013
732
100
Not more challenging, but easier, it’s for longer FL’s that the short flange distance doesn’t matter much.
I was thinking I had read the shorter flange distance creates issues for UWA lenses because it requires a high angle of incidence for the light striking the sensor. However, when you think about it, I assume if extra distance to the sensor was needed, the lens could just be designed with a longer barrel, so it is hard to see why it should be an issue.
 
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Viggo

EOS 5D SR
Dec 13, 2010
4,172
734
I was thinking I had read the shorter flange distance creates issues for UWA lenses because it requires a high angle of incidence for the light striking the sensor. However, when you think about it, I assume if extra distance to the sensor was needed, the lens could just be designed with a longer barrel, so it is hard to see why it should be an issue.
Hm, that sounds logical.. so perhaps that’s why they released the 35, 50, and 85 because it’s only midrange the RF mount is good for. And maybe that’s why the 28-70 isn’t 24. :p
 

tron

EOS 5D SR
Nov 8, 2011
4,031
338
I compared it with 16-35mm 2.8L III because I do have it. The 2.8L III is much better. Although there is no choice for the 30Mp EOS R with adapter (or for the 5DIV) for the EF lens, I checked with both the 21Mp 1DxIII and the 50Mp 5DsR. Same impression.

The EF lens wins with a difference. Now although I long for IS I might relax and save money (for now) :cool:
 
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Act444

EOS 6D MK II
May 4, 2011
993
102
Do you think people have any kind of patience to wait three generations for a decent uwa for RF? No, this is it for the next 10-12 years at least, and it has to be at least matching the 16-35 L III.
And I don’t disagree with you...
 
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BillB

EOS 6D MK II
May 11, 2017
1,140
380
Wow, a bit underwhelming to be honest but need more takes/reviews to be sure.

Let's not forget that with the EF version it took them 3 iterations to "get it right" - the first 2 versions were quite meh as well, as was the 17-40. Maybe the RF design poses new challenges in this realm..? Would one get better results adapting the EF 2.8 III instead? I'd like to see that comparison.
Flat chart assessments on wide angles can be flaky.
 

koenkooi

EOS 7D MK II
Feb 25, 2015
459
271
Wow, a bit underwhelming to be honest but need more takes/reviews to be sure.

Let's not forget that with the EF version it took them 3 iterations to "get it right" - the first 2 versions were quite meh as well, as was the 17-40. Maybe the RF design poses new challenges in this realm..? Would one get better results adapting the EF 2.8 III instead? I'd like to see that comparison.
The simulated MTF charts Canon published for the RF15-35 don't really show improvements compared to the EF16-35. But that's simulated MTF at 15mm on the RF compared to 16mm on the EF, so not exactly the same thing and computer generated as well.
 

tron

EOS 5D SR
Nov 8, 2011
4,031
338
We have to wait of course but TDP initial test is a little disappointment. And there is Roger from LensRentals that we will have to wait for him to test some copies in order to reach to a conclusion :)
 
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Reactions: Cwall64
Mar 14, 2012
2,294
180
I suspect it has something to do that default sharpening with R is lower, I’ll try and find a quote (y)
Take a look at the comments below at the TDP linked below. Bryan attributes the difference to the sharpening difference between the R and the 5DSr and gives a comparison of the 200 f/2 on both cameras. You see a similar trend where the R is blurrier. The MTFs are comparable to the 16-35 III, which is really good at resolution, so no surprise there -- they are the same generation. Bryan also intends on keeping it as part of his personal kit. So if one factors in the difference in sensor processing, which suggests that the two should perform similarly, and take into account that the RF version goes slightly wider and has IS... and costs more (at least initially), then the trade is first adopter premium for IS and 1mm on the wide end. For those with the funds and a R-centric kit, it makes sense.

Now if the R had the frame-rate of the M6 II... then I'd be all in on the R-ecosystem.