Opinion: Love it or Hate it, Digital Correction is here to Stay

Main thing I don’t understand with the Digital Corrections is how they can clearly make a physical crop of the original image and discard that data, yet still show 6000x4000 pixels in the final image.
Yes, it’s cropped…after the distortion correction stretches it out. Because of the 3:2 aspect ratio, correcting the distortion stretches the image more horizontally than vertical. In the case of a 24 MP sensor, it’s cropped down to 6000 pixels wide. For example, if you don’t crop to the original aspect ratio then the resulting corrected image is wider than 6000 pixels.

Note that this is just how barrel distortion correction works, even on EF lenses (example here).

I mean, conceptually I get that they’re stretched and interpolated. But not all of the original pixels are there. It’s a crop of what was captured.
Yes, stretched and interpolated just enough to get to the full sensor height, then the sides are (optionally) cropped off down to the full sensor width.

The other point is that all of the original light is there, it just didn’t initially cover all of the available pixels of the sensor.
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Opinion: Love it or Hate it, Digital Correction is here to Stay

Were you not stopping down? I thought that was typical for landscape shooting?

....
And I thought that these 'digital correction' allows for a better image quality as most writers assume. And now I can only use these expensive 'digital correction' lenses after stopping down?? That doesn't make sense!
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Opinion: Love it or Hate it, Digital Correction is here to Stay

Main thing I don’t understand with the Digital Corrections is how they can clearly make a physical crop of the original image and discard that data, yet still show 6000x4000 pixels in the final image.

I mean, conceptually I get that they’re stretched and interpolated. But not all of the original pixels are there. It’s a crop of what was captured.

I’m not saying it bothers me a lot. I just don’t understand it. But some of my favorite travel shots were taken with the much maligned 24-240 (which I think, based on the comments at release, invented distortion and lens corrections).
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Opinion: Love it or Hate it, Digital Correction is here to Stay

I see that there is an advantage with the digital correction for many applications, but there is also a disadvantage for other applications. It would be nice if we would have a larger selection of RF lenses so that each user would be able to select according to his needs (like in the good old 'EF-time').
Yes, let's go back to the good old days when men were men and lenses were lenses. When real men looked through real viewfinders. When sensors could be film and a manly man's lens knew it. Back then, we had optically corrected lenses that didn't need no stinkin' badges or digital correction. Manly man lenses like the Canon EF 11-24mm f/4 that had manly barrel distortion of 4.5%, or the even more manly manny Sigma 12-24mm f/4 Art with an even more massively manly 5.3% barrel distortion (the same as the Canon RF 14-35 that 'requires' correction, oh my!).

Lenses for MEN.png

Meh. I'll stay here in the present, thanks.
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Opinion: Love it or Hate it, Digital Correction is here to Stay

I have had landscaped photos ruined because of not realizing the amount of corner vignetting correction that was taking place.
Were you not stopping down? I thought that was typical for landscape shooting?
That said, I hate the concept of digital correction because of not where it is today but rather than where it could go tomorrow. What is stopping them from making smaller lenses yet that have an APS-H image circle and then they stretch/scale it back to your full frame resolution.. should we care if ultimately the image is cleaner, sharper, etc.. I would on principle.. but if they took away the toggle to see the file without corrections we would probably never know.
Slippery slope fallacy?
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Opinion: Love it or Hate it, Digital Correction is here to Stay

Concerning the distortion correction: When I apply the classical 'distortion correction' before stacking (e.g. startrails), I get ugly moire pattern in the stack. So it seems that stretching is introducing subtle variations into the image which will only show up when stacking.
Can you stack uncorrected subframes? Something like: process raw without the lens profile, then stack, then apply the corrections to the finished stack, if you want?
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Opinion: Love it or Hate it, Digital Correction is here to Stay

Hi!

As mentioned by some contributors before: The vignette is pretty strong and limiting the use of such lenses for certain applications like night photography. I have a lot of experience with different lenses and a vignette of around 3EV is the limit for my work of panoramas at night.

Concerning the distortion correction: When I apply the classical 'distortion correction' before stacking (e.g. startrails), I get ugly moire pattern in the stack. So it seems that stretching is introducing subtle variations into the image which will only show up when stacking.

I see that there is an advantage with the digital correction for many applications, but there is also a disadvantage for other applications. It would be nice if we would have a larger selection of RF lenses so that each user would be able to select according to his needs (like in the good old 'EF-time').
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Opinion: Love it or Hate it, Digital Correction is here to Stay

Definitely in the “hate it” side of this argument.. sure barrel distortion correction is lovely, and the ability to crop anywhere in an image to make a smaller also perfect image is something I do constantly… and you would think that being a EE with a specialization in DSP and image processing I would be all about this technology and pushing the boundaries….

But at the end of the day it all boils down to awareness of whats actually happening in the processing pipeline so that I, the photographer, can make the correct decision regarding exposure.. I have had landscaped photos ruined because of not realizing the amount of corner vignetting correction that was taking place. Now to be fair, I’m a hobbyist and those photos being ruined cost me nothing more than frustration..

That said, I hate the concept of digital correction because of not where it is today but rather than where it could go tomorrow. What is stopping them from making smaller lenses yet that have an APS-H image circle and then they stretch/scale it back to your full frame resolution.. should we care if ultimately the image is cleaner, sharper, etc.. I would on principle.. but if they took away the toggle to see the file without corrections we would probably never know.

I know I’m on the minority side of this argument.. and also that I shouldn’t care how the proverbial sausage is made.. but I’d like the believe that the these lenses don’t rely on post processing to stretch and brighten the image back to something acceptable to view.
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Opinion: Love it or Hate it, Digital Correction is here to Stay

The VCM lenses are crazy good! I love my 50mm and find myself reaching for the 85mm F2 a lot less...
Does the VCM 50/1.4 require digital corrections to stretch image corners that do not cover the entire sensor? or just some geometry correction and lightening up vignetting?
I believe people on the internet will keep the debate going forever, just so they have something to complain and talk about.
or what, should we do away with forum such as CR? :p
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Opinion: Love it or Hate it, Digital Correction is here to Stay

I've given up on Topaz for upscaling (and for everything else as well)- its more recent AI "improvements" invent too much. PS is much more realistic. I posted some examples comparing them on a thread somewhere, which I can't find.
Thanks. I upscale so rarely, I haven’t used Topaz in months.
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Opinion: Love it or Hate it, Digital Correction is here to Stay

Well over a decade ago, I wondered how long the DR debate would go on.

Some debates will never die, they feed too many click loving "experts". ;)
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Opinion: Love it or Hate it, Digital Correction is here to Stay

As does Topaz. I have not used and have no intention of ever using Canon's digital tele-converter.
I've given up on Topaz for upscaling (and for everything else as well)- its more recent AI "improvements" invent too much. PS is much more realistic. I posted some examples comparing them on a thread somewhere, which I can't find.
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Opinion: Love it or Hate it, Digital Correction is here to Stay

I want to make clear my discussion pertains to in-camera lens correction for JPEG output. My attachment sample is for chromatic aberration, but my point also applies to vignetting and geometric distortion.

Canon lens designers, with their Computer Aided Design (CAD) software, know exactly how a theoretical lens design performs regarding various aberrations. The lens design process involves numerous compromises to get to a marketable product.

One important lens design consideration is how easy it is to manufacture. A follow on from this is how consistent is unit to unit performance.

The in-camera lens correction software algorithm uses a ‘model’ of the lens to modify the internal RAW sensor data for JPEG engine output. Any ‘deviation’ of a particular lens being corrected from the model of that lens will result in a sub optimal corrected result.

My attachment is an EF 17-40mm f/4 L lens at 17mm and f/4. Top is software correction off and bottom is chromatic aberration correction on. The left and right sides are magnified crops of the left and right sides of an image of two framed photos – the frame is black and the matte board is white.

The uncorrected image clearly shows evidence of chromatic aberration with magenta and green fringing along the photo frame edges. However, on the corrected image, the magenta and green flip sides, albeit with a better result than non-corrected.

My conclusion is that my copy of the EF 17-40 doesn’t conform to the software model exactly. It’s overcorrected, so my copy is ‘better’ than the model, ha ha.

I understand post processing RAW gives one more flexibility regarding corrections, but my workflow is mostly JPEGs. In that regard, I’m greatly appreciative of in-camera software corrections.

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Opinion: Love it or Hate it, Digital Correction is here to Stay

That's absolutely right. As you wrote, in film times, optical correction was a necessity, lens manufacturers didn't have a choice.
Yet, when I see how good the VCM lenses have become, "despite" software correction,
The VCM lenses are crazy good! I love my 50mm and find myself reaching for the 85mm F2 a lot less...
I wonder how long the debate optical vs. software can still go on...
I believe people on the internet will keep the debate going forever, just so they have something to complain and talk about.
Personally, I´ve made up my mind: I love digital correction! The results with the 16mm, 14-35mm and now 50mm are just marvelous! The weight savings are amazing and very welcome.
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Opinion: Love it or Hate it, Digital Correction is here to Stay

What some are missing is that the 14-35L is an absolutely phenomenal lens. It is the best UW zoom I've ever owned/tried (I'm not including UUW lenses like the 11-24/10-24, which I have never used), and it's better than the 15-35L, which I also owned. As others have mentioned, the uncorrected lens is wider than 14mm (it may be closer to 13mm than to the 13.5mm already mentioned), so I struggle to find problems with the corners that are "cutoff" with correction
I agree to 100%. I have owned both, I chose the 14-35mm and sold off the 15-35mm. Never regretted it.
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Opinion: Love it or Hate it, Digital Correction is here to Stay

Or look at the EF 100-400L vs the RF 100-400. The RF is much lighter, yes, but the EF is sharper and cheaper. And that's considered one of the best value RF lenses around.
I choked hard when I read the comment. Even the mki version from 1998 sells for around 630 - 680 €, whereas the RF 100-400mm sells used for around 500-580 €. The 100-400mm mki is nearly 30 years old and some of it is features (inferior IS, push zoom) are outdated. It actually should be cheaper, but it is not. Used copies of 100-400mm mkii start at 1.300 € and go all the way up the 1.800 €. That should be the lens to compare it with because IS is similar and the zoom design as well.
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Here We Go Again, More EOS R3 Mark II Chatter

"I haven't talked to anyone that thinks there will ever be a Mark II of the R3."
Except for the people here on this forum who think there will be one. They can't agree on what it will be, but they are sure we'll see it.

Actually, in one way they can agree on what it will be...the camera they personally want. It's just that they all want something different.
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The Canon EOS R7 Mark II is in the Wild

I think we both agree that a mark two R3 in its current form doesn't seem to have a logical place in the current Canon lineup. The original EOS 3 was not a gripped body, nor was the EOS 1 for that matter, but times, circumstances and requirements change.
You're ignoring a couple of rather important differences. The EOS 3 was a film camera, not a digital camera (#D) or a mirrorless camera (R#). More importantly, the EOS 3 launched in 1998 – it was over two decades and literally a generation (in people terms) before the R3 and Canon's re-use of the series numeral.

So, as the first R3 series is a gripped, budget R1 does that mean its form is written in stone from now on ? I don't think it has to be.
Written in stone from now on? No. But it seems far too soon given that the R3 is still current and being sold directly by Canon. Having an R3II that differs wildly from the model it's directly replacing in the lineup and nomenclature seems like a complete non-starter.

Form a commercial point of view I would have thought that a separate high mp model series would be a more attractive sales proposition than a higher res version of a current model, as Canon previously did with their 5Ds/sr.
Why? I think the point of the 5Ds/R was that it was a 5-series body. An very successful line for Canon, and they wanted to make the point that it was very much a part of that line but with a high MP sensor. I think the same applies today, with the still-successful 5-series.

Also, remember that you just didn't get Canon putting a crop sensor into the RF mount :);)
I didn't get it because of the very successful EOS M line. But Canon didn't keep that around, they killed it.
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Opinion: Love it or Hate it, Digital Correction is here to Stay

The Digital Tele-Converter function crops the image then upscales it back to the original MP count of the full sensor. No, it's not a replacement of a physical extender...but it's doing digitally what the physical extended is doing optically – taking the central portion of the image and magnifying it to fill the sensor.
Photoshop Generative Upscale does a reasonable 2x and 4x upscale as well.
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The Canon EOS R7 Mark II is in the Wild

I can't see an R3II of any sort, but if there's another 3-series it would have to be the R3II and would you really expect a MkII version of a gripped, low MP body to be a non-gripped, high MP body? I don't see how that makes any sense. On the other hand, Canon had the 5D series and came out with one of them that was high MP called the 5Ds. So why call a new, non-gripped high MP body an R3II instead of an R5s? I really just don't get it.
I think we both agree that a mark two R3 in its current form doesn't seem to have a logical place in the current Canon lineup. The original EOS 3 was not a gripped body, nor was the EOS 1 for that matter, but times, circumstances and requirements change. However, there is a perceived gap in the current Canon line up in that they do not offer a high mp body, that is a body that has a significantly higher resolution / output than the current model range. Form a commercial point of view I would have thought that a separate high mp model series would be a more attractive sales proposition than a higher res version of a current model, as Canon previously did with their 5Ds/sr. To this end, Canon have the 3 series position available, which makes sense from a marketing position as it would be below the 1 series but above the 5 series. Of course there is no physical different between an R5S and an R3 in virtually the same body but with a much higher res sensor, but that is marketing semantics. As you point out, Canon will know their margins and profits on the 5DS/sr, and perhaps they feel they could be more commercially successful next time.
So, as the first R3 series is a gripped, budget R1 does that mean its form is written in stone from now on ? I don't think it has to be.
Also, remember that you just didn't get Canon putting a crop sensor into the RF mount :);)
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Opinion: Love it or Hate it, Digital Correction is here to Stay

That is crop no full replacement of a physical Extender but points in the right direction
The Digital Tele-Converter function crops the image then upscales it back to the original MP count of the full sensor. No, it's not a replacement of a physical extender...but it's doing digitally what the physical extender is doing optically – taking the central portion of the image and magnifying it to fill the sensor.
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