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



## Joules (Sep 14, 2019)

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.


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## Sharlin (Sep 14, 2019)

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.


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## Del Paso (Sep 14, 2019)

Could explain the peculiar firmware...


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## ajfotofilmagem (Sep 14, 2019)

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.


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## Antono Refa (Sep 14, 2019)

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?


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## Mt Spokane Photography (Sep 14, 2019)

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.


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## Joules (Sep 14, 2019)

Antono Refa said:


> 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.


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## Viggo (Sep 14, 2019)

I didn’t even know this was an issue with any lens or any body. Quite frankly I’m a bit shocked. And I think it’s unacceptable. Wow.


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## PCM-madison (Sep 14, 2019)

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.


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## Joules (Sep 14, 2019)

PCM-madison said:


> 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.


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## Act444 (Sep 14, 2019)

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.


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## PCM-madison (Sep 14, 2019)

Joules said:


> 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.


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## neuroanatomist (Sep 14, 2019)

PCM-madison said:


> 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.


What I saw in the video looked like mechanical vignetting. I think the filter explanation is a likely one.


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## Antono Refa (Sep 15, 2019)

Joules said:


> 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.



Joules said:


> 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 (Sep 15, 2019)

PCM-madison said:


> 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?


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## Ozarker (Sep 15, 2019)

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.  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 (Sep 15, 2019)

CanonFanBoy said:


> 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 (Sep 15, 2019)

PCM-madison said:


> 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.


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## Joules (Sep 15, 2019)

ajfotofilmagem said:


> 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.


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## mkamelg (Sep 15, 2019)

Sharlin said:


> 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.





ajfotofilmagem said:


> 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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## Ozarker (Sep 15, 2019)

ajfotofilmagem said:


> 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.


I don't quite understand what you are saying, but I guess that is why my two RF lenses only weigh 3.15 and 2.63 pounds each.  Thank God for mirrorless computing power and lightweight lenses.  Seriously, what is inherent to mirrorless that makes them more powerful in computing power than a DSLR. I would have to argue nothing at all. The EF lenses I used to have were mostly from the DSLR era, not film. Every single film era lens I own (more than 40) are very light and small. Even my Mamiya/Sekor 400 mm f/6.3 preset (4 elements) weighs in at just 935gr/33oz.


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## SteveC (Sep 15, 2019)

CanonFanBoy said:


> I don't quite understand what you are saying, but I guess that is why my two RF lenses only weigh 3.15 and 2.63 pounds each.  Thank God for mirrorless computing power and lightweight lenses.  Seriously, what is inherent to mirrorless that makes them more powerful in computing power than a DSLR. I would have to argue nothing at all. The EF lenses I used to have were mostly from the DSLR era, not film. Every single film era lens I own (more than 40) are very light and small. Even my Mamiya/Sekor 400 mm f/6.3 preset (4 elements) weighs in at just 935gr/33oz.



I think he's saying that since an EF lens might be used on a film camera, the designers can't rely on software to fix its inherent distortion--the film wouldn't be corrected by it. (Someone else made the point that the purely optical viewfinder wouldn't be corrected, even on a digital camera.) Therefore they have to put more glass in the lens itself. On an RF the software can not only correct the shot image, but it can correct what you see through the viewfinder, too, leaving no trace of what the camera did. Certainly the RF lenses have (up to this point) been bulky, but apparently this one is the first one to rely on software. It may be bulky but it is a 10x full-frame zoom, and that accounts for the bulk by itself.

As a side note I own a Tamron 18-400 which is over 20x zoom, and it's not nearly this distorting (according to the same reviewer). But it is a crop-frame lens; who knows how bad it would be on a full frame sensor?


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## SecureGSM (Sep 15, 2019)

neuroanatomist said:


> What I saw in the video looked like mechanical vignetting. I think the filter explanation is a likely one.


Or lens hood


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## neuroanatomist (Sep 15, 2019)

SecureGSM said:


> Or lens hood


Possibly, but the vignetting seemed symmetrical across the four corners, and an improperly installed petal-shaped hood causes asymmetrical vignetting.


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## wockawocka (Sep 15, 2019)

neuroanatomist said:


> What I saw in the video looked like mechanical vignetting. I think the filter explanation is a likely one.



The RF35 has quite severe vignetting when using a lens hood as well.


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## Ozarker (Sep 15, 2019)

SteveC said:


> I think he's saying that since an EF lens might be used on a film camera, the designers can't rely on software to fix its inherent distortion--the film wouldn't be corrected by it. (Someone else made the point that the purely optical viewfinder wouldn't be corrected, even on a digital camera.) Therefore they have to put more glass in the lens itself. On an RF the software can not only correct the shot image, but it can correct what you see through the viewfinder, too, leaving no trace of what the camera did. Certainly the RF lenses have (up to this point) been bulky, but apparently this one is the first one to rely on software. It may be bulky but it is a 10x full-frame zoom, and that accounts for the bulk by itself.
> 
> As a side note I own a Tamron 18-400 which is over 20x zoom, and it's not nearly this distorting (according to the same reviewer). But it is a crop-frame lens; who knows how bad it would be on a full frame sensor?


True on the film cameras, but unless I am mistaken, many of the newer DSLR's also provide in camera lens corrections... though the viewfinder is another story.

In a way, I would rather not have the corrections most of the time for myself. I never check the correction box in Lightroom. I can't remember if it was the EF 35mm f/1.4L II or my EF 24-70 f/2.8L II, but one of them never showed any correction when I would check the box. So maybe the lens was already corrected in my 5D Mark III?

Anyway, I tend to add vignette a lot. I just like it. And for me, sometimes the lens distortion looks better uncorrected on some lenses. Then again, I don't generally shoot landscapes or architecture, just people.

As I learn my R better, I'll have to see whether I can turn off the corrections and see how it looks. That might be fun.


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## neuroanatomist (Sep 15, 2019)

wockawocka said:


> The RF35 has quite severe vignetting when using a lens hood as well.


Does the hood increase the vignetting? That would be surprising.


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## Karlbug (Sep 15, 2019)

I downloaded RAW file from DPReview's gallery for RF24-240 (https://www.dpreview.com/sample-gal...-rf-24-240mm-f4-6-3-sample-gallery/8982014006), loaded it into Lightroom and exported WITH and WITHOUT corrections.

Here are results.


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## SteveC (Sep 15, 2019)

angrykarl said:


> I downloaded RAW file from DPReview's gallery for RF24-240 (https://www.dpreview.com/sample-gal...-rf-24-240mm-f4-6-3-sample-gallery/8982014006), loaded it into Lightroom and exported WITH and WITHOUT corrections.
> 
> Here are results.



Yikes! There's a stripe down the back of that guy's shirt in the uncorrected version, that gets removed in the correction. In the upper right, the angle of the track beyond the curve is different.


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## privatebydesign (Sep 15, 2019)

Yes many of Lightroom's 'corrections' are clumsy at best. They try to force a true rectilinear projection on lenses that often were not designed to do that because off the field of view.




angrykarl said:


> I downloaded RAW file from DPReview's gallery for RF24-240 (https://www.dpreview.com/sample-gal...-rf-24-240mm-f4-6-3-sample-gallery/8982014006), loaded it into Lightroom and exported WITH and WITHOUT corrections.
> 
> Here are results.





SteveC said:


> Yikes! There's a stripe down the back of that guy's shirt in the uncorrected version, that gets removed in the correction. In the upper right, the angle of the track beyond the curve is different.


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## Viggo (Sep 15, 2019)

This is absurd to me.....


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## privatebydesign (Sep 15, 2019)

Viggo said:


> This is absurd to me.....


What is?


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## Viggo (Sep 15, 2019)

privatebydesign said:


> What is?


The lens is faked into to working... never seen anything like it...


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## privatebydesign (Sep 15, 2019)

Viggo said:


> The lens is faked into to working... never seen anything like it...


Hey people have been demanding Canon give all those Sony features, this is the sh!t that results when people who don't know or care make up the lions share of the market. Canon have been forced into compromises like this by the market, so who should we blame?


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## SecureGSM (Sep 15, 2019)

privatebydesign said:


> Hey people have been demanding Canon give all those Sony features, this is the sh!t that results when people who don't know or care make up the lions share of the market. Canon have been forced into compromises like this by the market, so who should we blame?


Not typical of Canon. Something is not adding up here. I do not have a lens to play with but I am sure that this issues will be explained.


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## SteveC (Sep 16, 2019)

SecureGSM said:


> Not typical of Canon. Something is not adding up here. I do not have a lens to play with but I am sure that this issues will be explained.



In this case, I'm gathering: Canon felt a demand for a 10x zoom. Canon felt it needed to be cheap. This was the only way to do it. They tend to prefer solving problems in hardware (the optics) rather than software, but they couldn't do that here, not and sell the lens for a non-stratospheric price.

There's an RF camera in my distant future, I think...but the RF lenses are almost all more expensive than I can justify to myself--I'll be using a lot of adapters on EF lenses (many of which are reasonable and/or do things no RF lens can do yet, e.g., the 100-400 II--which is still on my want list).


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## PCM-madison (Sep 16, 2019)

I'm very curious how and if this issue shows up in future reviews by Brian at TDP and Roger at lensrentals whose reviews I most respect. For me, an issue that only shows up using non-compatible RAW conversion is a non-issue for my workflow.


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## Joules (Sep 16, 2019)

PCM-madison said:


> For me, an issue that only shows up using non-compatible RAW conversion is a non-issue for my workflow.


This really isn't an issue. It is just a way of designing a lens that we have not seen from a Canon ILC lens before. It surprised me personally, but if it allows Canon to deliver a lens that seems to be a great value otherwise, I'm all for doing more with software and hopefully some computational photography techniques in the future.

The only true issue I see here is that you give up a bit of sensor area to allow for that crop. So you are not really getting an FF image and therefore your signal is lower and your Signal to noise ratio slightly worse. And you aren't getting your full sensor resolution either. That's a bit cheeky from Canon, to call it an FF 10x zoom, when in truth they basically shrink your sensor to match the projected size on the wide end.


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## Joules (Sep 16, 2019)

SecureGSM said:


> Not typical of Canon. Something is not adding up here. I do not have a lens to play with but I am sure that this issues will be explained.


Have you looked at the pictures in link from  this post?

I don't see what explanation other than the given one could make sense. The lens is wider than 24mm but doesn't cover the whole sensor on the wide end. So the image is cropped to the area that delivers a 24mm equivalent FoV.

This also explains why a new firmware was required to use this lens, as this cropping feature was probably ommited on launch because it was a low priority feature that the lenses so far didn't need.

Something not being typical doesn't mean Canon can't do it. They are working with a new market now, and have different requirements as well as different options to satisfy them.


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## SecureGSM (Sep 16, 2019)

SteveC said:


> In this case, I'm gathering: Canon felt a demand for a 10x zoom. Canon felt it needed to be cheap. This was the only way to do it. They tend to prefer solving problems in hardware (the optics) rather than software, but they couldn't do that here, not and sell the lens for a non-stratospheric price.
> 
> There's an RF camera in my distant future, I think...but the RF lenses are almost all more expensive than I can justify to myself--I'll be using a lot of adapters on EF lenses (many of which are reasonable and/or do things no RF lens can do yet, e.g., the 100-400 II--which is still on my want list).


A lot of assumptions that do not make a lot of sense or aren’t typical of Canon. Sorry. This is not Canon.


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## Joules (Sep 16, 2019)

SecureGSM said:


> This is not Canon.


Could you specify what isn't Canon? Are you saying that you don't believe this effect is caused by the lens?


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## SecureGSM (Sep 16, 2019)

Joules said:


> Could you specify what isn't Canon? Are you saying that you don't believe this effect is caused by the lens?


I am not interested in this conversation. However, the proposed cause of this issue sounds way too opportunistic for a risk averse enterprise. Read : Canon.


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## andrei1989 (Sep 16, 2019)

i'm curious of one thing though: has anyone tried mounting the lens and then twisting back a bit so that it doesn't get recognized by the camera anymore so that it doesn't apply any corrections? that would be the simples and most objective test i can think of, eliminating any raw converters and such..


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## Kit. (Sep 16, 2019)

SecureGSM said:


> A lot of assumptions that do not make a lot of sense or aren’t typical of Canon. Sorry. This is not Canon.


Is G7X II Canon? Because its lens works in the same way (not that Sony RX100V lens is any different).


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## SecureGSM (Sep 16, 2019)

Kit. said:


> Is G7X II Canon? Because its lens works in the same way (not that Sony RX100V lens is any different).


small sensor fixed lens point and shoot vs an R camera with a FF lens attached. ok. i see a logic here.


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## Kit. (Sep 16, 2019)

SecureGSM said:


> small sensor point and shoot with fixed lens vs an R camera with a FF lens attached. ok. i see the logic here.


Personally, I see a logical fallacy here. "No true Scotsman" fallacy, to be precise.


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## SteveC (Sep 16, 2019)

SecureGSM said:


> I am not interested in this conversation. However, the proposed cause of this issue sounds way too opportunistic for a risk averse enterprise. Read : Canon.



For someone "not interested in this conversation" you've been devoting a fair amount of effort to telling participants in it that they are wrong. Though you've not followed through and supplied anything to support that. Maybe that's what you're not interested in doing.

Don't misunderstand me; if I am _demonstrably_ wrong, I want to know it. But I'm not going to conclude I was wrong on the basis of some guy on the internet who isn't interested in backing up an _assertion_ that I am wrong.


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## Don Haines (Sep 16, 2019)

DPR photo shows some extreme vignetting at 24mm. Other people's shots do not show it.

The logical thing to do is to wait until other (and more trusted) sources weigh in.


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## ethanz (Sep 16, 2019)

I don't really see a problem here. Sure it is unfortunate to some of us with L lenses that this would happen. But for a 10x zoom non L lens that is at a cheap price, I think the results look pretty good. Lots of people outside this forum would be very happy with the results they get.


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## stevelee (Sep 16, 2019)

Even with the G7X II, I sometimes go back and forth between profile lens corrections on and off in ACR. Sometimes that leads me to lessen and sometimes to increase some settings. I'd rather do that than have another couple pounds of glass to do lens corrections. Sometimes after I've altered perspective, such as converging verticals, I need to nudge the correction a bit toward the pincushion direction to straighten the lines. I think the profile slightly undercorrects barrel distortion.


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## koenkooi (Sep 16, 2019)

I was at the Canon booth at IBC today and I still don't know whether I like the 24-240 more than the 24-105 or not. Similar price, size and weight. I don't mind the heavy software corrections, but I don't know how often I'll use the 105-240 range.


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## YuengLinger (Sep 16, 2019)

Don Haines said:


> DPR photo shows some extreme vignetting at 24mm. Other people's shots do not show it.
> 
> The logical thing to do is to wait until other (and more trusted) sources weigh in.


And what exactly does "logic" have to do with anything? Hmmmm?


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## SecureGSM (Sep 16, 2019)

SteveC said:


> For someone "not interested in this conversation" you've been devoting a fair amount of effort to telling participants in it that they are wrong. Though you've not followed through and supplied anything to support that. Maybe that's what you're not interested in doing.
> 
> Don't misunderstand me; if I am _demonstrably_ wrong, I want to know it. But I'm not going to conclude I was wrong on the basis of some guy on the internet who isn't interested in backing up an _assertion_ that I am wrong.


You are a demonstrably wrong sorry. 
I expressed my opinion ( made a single short comment) but not in a position to engage in arguments or have time for responding to Rhetorical questions. 
I do not see this being devoting a fair amount of effort. 
I Hope this explains.


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## SteveC (Sep 16, 2019)

SecureGSM said:


> You are a demonstrably wrong sorry.
> I expressed my opinion ( made a single short comment) but not in a position to engage in arguments or have time for responding to Rhetorical questions.
> I do not see this being devoting a fair amount of effort.
> I Hope this explains.



I may be demonstrably wrong...but as you haven't demonstrated it...dismissed.


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## PCM-madison (Sep 17, 2019)

PCM-madison said:


> 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


Upon further testing by opening RAW photos from my lens at 24mm F4 using different RAW converters, I can confirm that my lens shows mechanical vignetting or not depending on the RAW conversion pathway. All of the final images are 6240X4160 so there is clearly some cropping and up-scaling for some RAW conversion pathways that I was not aware of.


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## Mt Spokane Photography (Sep 17, 2019)

So the lens profile correction in Adobe camera raw straightens the distortion which crops the photo and removes viginetting. Apparently DPP does the same, I do not have DLO corrections for the lens, they must be embedded in the cr3 file.

I don't think that's a issue for me, but how wide actually is the final image? 

If the hype over the distortion at 24mm causes a drop in sales and a drop in price, I'll get one.


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## Mt Spokane Photography (Sep 17, 2019)

PCM-madison said:


> Upon further testing by opening RAW photos from my lens at 24mm F4 using different RAW converters, I can confirm that my lens shows mechanical vignetting or not depending on the RAW conversion pathway. All of the final images are 6240X4160 so there is clearly some cropping and up-scaling for some RAW conversion pathways that I was not aware of.




Is it a big deal to you? The lens is weak at 24mm, but the corrected images don't look bad to me. I would not be buying this lens for critical work, just as a walk around do it all lens.

Does it take a TC?


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## Kit. (Sep 17, 2019)

Mt Spokane Photography said:


> Does it take a TC?


Are there RF TCs?


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## Michael Clark (Sep 17, 2019)

"Why can't Canon be more like Sony, Panasonic, and Olympus?"

Canon: Here, try this cheap and relatively light 24-240 lens.

"OMG!!!! Canon is doing the same thing that Sony, Panasonic, and Olympus have been doing for years!!!!"

"Canon is *******!"


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## SecureGSM (Sep 17, 2019)

SteveC said:


> I may be demonstrably wrong...but as you haven't demonstrated it...dismissed.


That’s because you are relatively new to this game and you have admitted that earlier. Have merely expressed my opinion and di not want to engage in meaningless conversation. That’s all.


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## SteveC (Sep 17, 2019)

SecureGSM said:


> That’s because you are relatively new to this game and you have admitted that earlier. Have merely expressed my opinion and di not want to engage in meaningless conversation. That’s all.



For someone not wanting to engage in this conversation, you sure seem determined to have the last--albeit empty of meaningful information--word.

And, as someone who IS indeed new to this game, I can still draw from my experience dealing with people in other fields. I recognize when someone is being a blowhard claiming to know things but refusing to justify them, _claiming_ it's because he just doesn't feel like it (not worth the effort, don't you see), but willing to put effort into trying to assert he just knows and I should just shut up and accept his authority.


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## Mt Spokane Photography (Sep 17, 2019)

Kit. said:


> Are there RF TCs?


Good point. I wonder when they will be coming. With the 70-200 arriving, they should arrive soon. They are relatively simple lenses, so they should be coming. This might be a opportunity for a 3rd party lens maker.


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## SecureGSM (Sep 18, 2019)

SteveC said:


> For someone not wanting to engage in this conversation, you sure seem determined to have the last--albeit empty of meaningful information--word.
> 
> And, as someone who IS indeed new to this game, I can still draw from my experience dealing with people in other fields. I recognize when someone is being a blowhard claiming to know things but refusing to justify them, _claiming_ it's because he just doesn't feel like it (not worth the effort, don't you see), but willing to put effort into trying to assert he just knows and I should just shut up and accept his authority.


can you please go back to my original post ans see what I actually said. I did not claim anything. here for your convenience:


> Not typical of Canon. Something is not adding up here. I do not have a lens to play with but I am sure that this issues will be explained.



i selectively choose what to respond and what to not respond. I respond to your aggressive post referencing some of your experience dealing in with people in other field, which is nothing to do with optics or photography obviously therefore you have evidently no enough experience or knowledge to do a judgement.
sorry you asked for it.


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## SecureGSM (Sep 19, 2019)

Wow. Ok noted


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## Optics Patent (Dec 16, 2019)

andrei1989 said:


> i'm curious of one thing though: has anyone tried mounting the lens and then twisting back a bit so that it doesn't get recognized by the camera anymore so that it doesn't apply any corrections? that would be the simples and most objective test i can think of, eliminating any raw converters and such..



Ask and ye shall receive. Corrected in camera:



With lens disconnected enough to decouple electronics:



This looks like it is cropping about 7-8% of the sensor width. I didn't measure whether the resulting image size correctly reflects what an ideal 24mm lens would show, but I presume so. This image subject (bonus points for identifying the object on the tripod) is dark in the corners, and on a bright-cornered subject I observed zero evidence of vignetting as shown in the racetrack photo.

This 24-240 cost me only $500 as the kit lens with a recent RP purchase, and I consider it a technical miracle that as an imagine system this and a modern body can generate such distortion and aberration free images for this package at this price. I scratch my head at the reviews that show what aberrations you can get if you use a lens like virtually no one ever will. 

The 24-240 isn't getting much use, as I use the new 70-200 for most things, or the noisy 35mm f1.8. If I get a mid-range f2.8 zoom I might let the 24-240 go.


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## Optics Patent (Dec 16, 2019)

Mt Spokane Photography said:


> Good point. I wonder when they will be coming. With the 70-200 arriving, they should arrive soon. They are relatively simple lenses, so they should be coming. This might be a opportunity for a 3rd party lens maker.



I don't see a big demand for a RF-RF TC on the shorty 70-200. I'll speculate that the lightened 300mm f2.8 IS III that brings all the lightening of the 400 will be an RF/EF model, using my patent pending concept of a removable adapter that makes it cheaper than if they stocked two models. As the first RF super-telephoto this will include the launch of the first RF TC. And I will then retire on the royalties.

A better notion in the meantime is an EF-RF TC and adapter that lets us put existing super-teles on the R - with appropriately integrated styling. That might include a 1X "TC" that is a better-styled adapter for white lenses.


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## koenkooi (Dec 16, 2019)

Optics Patent said:


> [..] I didn't measure whether the resulting image size correctly reflects what an ideal 24mm lens would show, but I presume so.[..]


Someone of the dpreview forum compared it to the 24mm and 24-70 and he estimated it to be 22mm when uncorrected.


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## StoicalEtcher (Dec 16, 2019)

Optics Patent said:


> And I will then retire on the royalties.


 Good luck - I actually like that idea, so hope it works out!


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## Optics Patent (Dec 17, 2019)

StoicalEtcher said:


> Good luck - I actually like that idea, so hope it works out!


Thanks. One key concept is that the TC detach from the lens is internal or otherwise avoids accidental disconnection. Must remove lens and TC combo from body before separating TC from lens. And one would certainly want to see clean visual integration with the lens and with the body, which most TCs and RF adapters fail at.


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## andrei1989 (Dec 17, 2019)

Optics Patent said:


> Ask and ye shall receive.



thanks for that
the uncorrected image looks distorted and has some vignetting but not like how it was shown in some videos
and if the end result is still 24mm...does it matter how it was achieved?

telescope equatorial mount. can i have my cookie now?


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