RF 24-240mm: No full frame cover at 24mm

Joules

EOS 7D MK II
Jul 16, 2017
619
577
Hamburg, Germany
Chris Frost has posted a review of that lens and it appears as if Canon made some interesting compromises in order to allow it to hit the price, weight and size point they amed for. Namely, at the wide end, it doesn't really cover the whole frame. That shocked me, to be honest. Is it something they have done before, maybe on an EF-M lens? Or is this a first?


I'm not really interested in the lens, even if I would get a R camera in the future. But it seems odd to me that are doing this. Seems like a cheap trick a third party manufacturer would pull. Seems like we could also see some really low cost RF lenses if this design mentality is carried over to less extreme designs, like a pancake lens.
 

Sharlin

EOS 6D MK II
Dec 26, 2015
1,209
867
Turku, Finland
Canon has done it before on PowerShots, but not on ILC lenses, I think. Other manufacturers definitely do it as well, the Sony E-mount 16-50mm kit lens is a particularly offensive example.
 
Aug 23, 2013
2,346
47
Bahia Brazil
To correct geometric distortion and vignetting in zoom lenses, more optical elements are used and result in expensive and heavy lenses. Since mirrosless has high computing power, you can make lens with uncorrected distortion and vignetting, and leave the job to the camera software. Such a thing could not be done with EF lenses, which need to be compatible with photographic film camera (mirrorless does not need). Canon first makes use of a tactic that Sony has been using for a long time.
 

Mt Spokane Photography

I post too Much on Here!!
Mar 25, 2011
15,710
880
I had not seen this mentioned so far at TDP, they have it up in their image quality tool, but have not yet done a review. I wonder if their sample images have the in camera corrections turned on. The lens is ugly at 24mm away from the center area, and also at 240mm.

The comparison with the 24-105 is interesting. The 24-240 is awful at 24mm, but seems to beat the 24-105 at 50mm and 100mm. I'm not sure how much of the CA's can be cleaned up in Lightroom.
 

Joules

EOS 7D MK II
Jul 16, 2017
619
577
Hamburg, Germany
Who would have believed a 10x superzoom priced <$1,000 has poor optical performance, esp in comparison to a 4x zoom with the exact same price tag?
Few people, probably.

I personally am just surprised to see Canon make such a heavy compromise on an RF mount lens. Before it has been my impression that RF is the System aimed at uncompromised optical performance and that people looking for small and light we're expected to go for EF-M.

It will be interesting how these systems will be separated in the future, especially if an APS-C RF camera actually emerges.
 

PCM-madison

EOS 80D
Dec 9, 2013
115
47
Distortion at 24mm, yes. Not covering full frame, false. EOS RP with 24-240mm at 24mm F4. RAW image processed in Adobe RAW with no lens correction.
24mm brick wall F4 s.jpg
 

Joules

EOS 7D MK II
Jul 16, 2017
619
577
Hamburg, Germany
Distortion at 24mm, yes. Not covering full frame, false. EOS RP with 24-240mm at 24mm F4. RAW image processed in Adobe RAW with no lens correction.View attachment 186607
Hm, interessesting. Does it show vignetting if you shoot a white backdrop? If it doesn't, the Raw file might be pre processed in camera.

Maybe there's also something wrong with Mr Frosts copy of the lens - although in that case, it seems odd that it only shows up in Adobe's app.
 

Act444

EOS 6D MK II
May 4, 2011
1,072
141
Wow. That a bit shocking to be honest.

I think there's just too many compromises for me in this one. The 24-105 (same price!) is already enough of a compromise lens, but at least still holds decent enough IQ at the important points. That one would probably be my travel choice if I were to shoot an R camera in the future.
 

PCM-madison

EOS 80D
Dec 9, 2013
115
47
Hm, interessesting. Does it show vignetting if you shoot a white backdrop? If it doesn't, the Raw file might be pre processed in camera.

Maybe there's also something wrong with Mr Frosts copy of the lens - although in that case, it seems odd that it only shows up in Adobe's app.
My RAW images have mild vignetting. I have never heard of Mr. Frost. Maybe it was poor technique like shooting wide angle with a filter installed that could block part of the image circle.
 

Antono Refa

EOS 6D MK II
Mar 26, 2014
930
174
Few people, probably.
I've read reviews of the EF 28-300mm (or was it the EF 35-350mm?), and at nearly 3x the price, it doesn't excel optically either.

I personally am just surprised to see Canon make such a heavy compromise on an RF mount lens. Before it has been my impression that RF is the System aimed at uncompromised optical performance and that people looking for small and light we're expected to go for EF-M.
Seems to me like the initial release of expensive high end lenses has created a bias.
 
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Joules

EOS 7D MK II
Jul 16, 2017
619
577
Hamburg, Germany
My RAW images have mild vignetting. I have never heard of Mr. Frost. Maybe it was poor technique like shooting wide angle with a filter installed that could block part of the image circle.
Pour technique seems unlikely to me. Mr Frost has been doing a really nice job with his lens review channel and is by far one of the most objective and respectful person among the YouTube photography community. Such a mistake would be very unusual for him.

And if it was a filter creating the effect, why does it clear up when the corrections are enabled? Do correction profiles suddenly know what darkness is actually due to the subject and what comes from a filter/bad hood/other obstacle, so that they can eliminate only the one and not the other? That seems like a break through in technology that would make it unnecessary for the guys at Adobe & Co to release a profile for each lens. If that's the case I at least missed the announcement.

Further more, if you look at the image without any corrections, shown at 6:30, you'll see that it gets wider than before. Sure, that can be achieved using filters, but like I said: Mr Frost has a good reputation and using such a hard manipulation would ruin that. Why would he deliberately put a manipulating filter in the lens and claim the effect it has was caused by the lens?

It seems more likely to me that Mr. Frost used an older Photoshop / ACR version that did not support the lens yet. On a new version, there likely are two corrections: stretch and crop to fill the frame and remove the vignetting / distortion affecting the stretched portion. The latter one is controlled in the correction profile section, the former is applied in general. If you have access to raw files from the lens, you could try to open them in a raw converter that doesn't have any profile out yet, if you happen to have access to such. Or isn't there also a way to open an older version of all the CC apps?
 

CanonFanBoy

Really O.K. Boomer
Jan 28, 2015
4,705
2,625
Irving, Texas
Relatively inexpensive lens with 10x zoom. Unsurprising results, in my opinion. Not too bad for what it is, really. I think many of us are very spoiled. There are some negatives and some positives. The RF 24-105mm f/4 is a much better choice. I wouldn't expect a lot from a super zoom. I would never buy one, but I would bet many will. It is what it is. The closest I ever got to a super zoom was an EF-s 55-250mm I think, and I was always very happy with the photos at that point. We tend to be very demanding around here. That isn't a bad thing, but most buyers probably don't analyze things as much as we do. This may be the only lens some people buy for their camera just because it covers so much range. That's why I got the 55-250 years ago (from Ritz camera in Twin Falls Idaho), now look at what an idiot I am. :ROFLMAO: Had it not been for this website, I'd probably still be sporting my old Canon XSi and thinking it is the best thing since sliced bread. I can remember my daughter telling me what an incredible camera that was. She has it now.
 
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Joules

EOS 7D MK II
Jul 16, 2017
619
577
Hamburg, Germany
We tend to be very demanding around here.
That's true. I honestly think the sharpness shown in the video for anything but the extreme corners is excellent.

But concerning the high demands here, there are also a lot of people who are writing that they want really tiny FF lenses. For example, a lens not sticking out further than the grip of the camera. And if Canon now is ready to make some compromise in the pure optical side of things that get's dealt with in software, maybe we'll actually see such lenses in the future.
 
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koenkooi

EOS 7D MK II
Feb 25, 2015
749
512
Distortion at 24mm, yes. Not covering full frame, false. EOS RP with 24-240mm at 24mm F4. RAW image processed in Adobe RAW with no lens correction.View attachment 186607
Have a look at the thread on the Fred Miranda forum. That shows that at 24mm it's a lot wider than 24mm and the camera sets a crop rectangle in the RAW file. If you look at the RAW file with e.g. RAWdigger you'll get the full FoV.

If you use the newest DPP (.50) you get a profile for the 24-240 for corrections and DLO.
 

Joules

EOS 7D MK II
Jul 16, 2017
619
577
Hamburg, Germany
Since mirrosless has high computing power, you can make lens with uncorrected distortion and vignetting, and leave the job to the camera software. Such a thing could not be done with EF lenses, which need to be compatible with photographic film camera
Somebody on the FM forum post linked by koenkooi (Thanks, didn't find that when looking for others reporting this effect) pointed out that pulling something like this on an EF lens with optical viewfinder would have resulted in a fair difference between what you see in the Viewfinder vs what your image ends up being. With the digital processing pipeline linked to an EVF and the 'What You see is What You get' approach, an additional constraint is removed for mirrorless lenses: They don't have to produce an image that matches the composition you'll end up with.

I've never thought of it that way.

I've read a comment on this forum somewhere of a guy that would like to have lenses that are entirely corrected for distortion with software, instead of additional elements, to cut down price and weight. Might not be as far fetched as I originally thought.
 

mkamelg

I'm New Here
Feb 1, 2015
23
10
Poland
Canon has done it before on PowerShots, but not on ILC lenses, I think. Other manufacturers definitely do it as well, the Sony E-mount 16-50mm kit lens is a particularly offensive example.
To correct geometric distortion and vignetting in zoom lenses, more optical elements are used and result in expensive and heavy lenses. Since mirrosless has high computing power, you can make lens with uncorrected distortion and vignetting, and leave the job to the camera software. Such a thing could not be done with EF lenses, which need to be compatible with photographic film camera (mirrorless does not need). Canon first makes use of a tactic that Sony has been using for a long time.
Both of you are right.

 
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