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The limits of "computational photography"

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Re: The limits of "computational photography"

#211

Post by jlarocco »

donkeyd wrote: post #64
kaba0 wrote: post #52

Earlier quoted context omitted.

Do digital cameras really do anywhere near the same computations? Like, they usually have like some low-end shitty microprocessor at most, while for example an iphone has an insanely powerful CPU. Sure, plenty part of this processing happens in the ISP, but surely not everything.

No, they don't. It's not just the CPU, it's also that phones will often take bracketed exposures and use sensor data to align them correctly and automatically create an HDR image, for example. Either that or taking lots of short exposures and stacking them. It's not just in post processing, the magic already happens while taking the image itself. People who think digital cameras do anything close to what modern phone…

Well somebody doesn't have a clue...

In camera HDR: https://www.slrlounge.com/in-camera-hdr-intro/

In camera focus stacking: https://www.youtube.com/embed/E5zX1E5wAiE

Sometimes high end "pro" cameras will skip those features because they expect people to process those image on a computer anyway, but in general a modern camera will beat a phone hands down.

Re: The limits of "computational photography"

#212

Post by _aavaa_ »

astrange wrote: post #210
buildbot wrote: post #201

Earlier quoted context omitted.

You are all over this thread trying to prove that iPhones somehow have a unique setup in the industry that no other camera can match, and people keep telling you how wrong you are. DNG is 100% and image format, and can be “raw” or completely processed depending on the layers internally. Educate yourself before making such blanket statements.

I know what a DNG is. It's not a final delivery format; it's not compressed and I don't think eg gaming content pipelines are going to accept it for ingest either. (Also, macOS won't display them in HDR, but will display EXR files in HDR. Some trivia for you.)

After this comment I get where you’re coming from.

Do you consider the heic files from an iPhone hdr files rather than sdr, even though the extra brightness channel is stored as a separate channel rather than extending the range of rgb values?

Re: The limits of "computational photography"

#213

Post by CarVac »

foldr wrote: post #145
CarVac wrote: post #93

Earlier quoted context omitted.

Afaik proraw has the same computational reconstruction, but none of the baked-in contrast, lighting, or color tweaks. This gives you a clean low-noise image with editing flexibility but it does have the flaws of deconvolution and stacking and AI denoising. Actual raw from a cell phone is insanely noisy and hideously soft from diffraction in the best of cases.

>Actual raw from a cell phone is insanely noisy and hideously soft from diffraction in the best of cases. You can get single shot RAW output from Halide and other third party apps on iPhones. It's actually perfectly usable and not particularly noisy or soft. I haven't personally had any problems with the output of ProRAW (which applies far less aggressive sharpening than the standard JPEG processing). I'm pretty sure…

Do you have any full resolution examples to share?

I'm comparing to large-sensor cameras on large 4k screens, of course.

What is "usable" or not varies dramatically depending on how large you display it.

Re: The limits of "computational photography"

#214

Post by buildbot »

astrange wrote: post #210
buildbot wrote: post #201

Earlier quoted context omitted.

You are all over this thread trying to prove that iPhones somehow have a unique setup in the industry that no other camera can match, and people keep telling you how wrong you are. DNG is 100% and image format, and can be “raw” or completely processed depending on the layers internally. Educate yourself before making such blanket statements.

I know what a DNG is. It's not a final delivery format; it's not compressed and I don't think eg gaming content pipelines are going to accept it for ingest either. (Also, macOS won't display them in HDR, but will display EXR files in HDR. Some trivia for you.)

-> It's not a final delivery format

linear DNG?

-> it's not compressed

"Lossless and lossy compression (optional): DNG support optional lossless and (since version 1.4) also lossy compression.[36] The lossy compression losses are practically imperceptible in real world images"

-> I don't think eg gaming content pipelines

Why is this a goalpost even??? In what context? Photogrammetry? DNG works just fine.... Or the actual engine itself? found one in 30 seconds of searching: https://github.com/EQMG/Acid

-> macOS won't display them in HDR

Well, that seems like a macOS problem

This is ridiculous at this point.

Re: The limits of "computational photography"

#215

Post by foldr »

CarVac wrote: post #213
foldr wrote: post #145

Earlier quoted context omitted.

>Actual raw from a cell phone is insanely noisy and hideously soft from diffraction in the best of cases. You can get single shot RAW output from Halide and other third party apps on iPhones. It's actually perfectly usable and not particularly noisy or soft. I haven't personally had any problems with the output of ProRAW (which applies far less aggressive sharpening than the standard JPEG processing). I'm pretty sure…

Do you have any full resolution examples to share? I'm comparing to large-sensor cameras on large 4k screens, of course. What is "usable" or not varies dramatically depending on how large you display it.

I’m comparing it to multi shot raw (i.e. ProRAW). What I mean to say is that if you would consider using a typical ProRAW or JPEG shot from an iPhone (both based on multiple exposures), then you would also consider using a single-shot RAW. At daylight ISOs the difference in noise and sharpness is small.

Here's a JPEG from a single shot 12MP RAW made with Halide (can't shoot 48MP single shot RAW for some reason): https://drive.google.com/file/d/1oqQB_UbdBaaoM3vC2IG_9jzP2AG...

Here's a JPEG from a ProRAW 48MP made with the camera app: https://drive.google.com/file/d/1oqQB_UbdBaaoM3vC2IG_9jzP2AG...

Here's a JPEG from a ProRAW 48MP made with Halide: https://drive.google.com/file/d/13GW_CIIvOSFEsKcON28Y34NgQAA...

All images are shot on an iPhone 14 Pro Max and processed in Lightroom (60 on the sharpening slider, no noise reduction). There are certainly many differences between the images, but it's not as if the single shot RAW is a total mess. In fact, in this case the single shot RAW is cleaner and better looking than the ProRAW output of Apple's camera app for the most part. It even has more textural detail in a couple of areas where Apple's processing has smoodged things. This could partly be because I was able to select ISO 57 using Halide, whereas the camera app chose to use ISO 100. (All images were shot on a tripod, so there was no real need to use a higher ISO.) As you can see, Halide's ProRAW doesn't smoodge quite as much. I generally prefer the Halide ProRAW to the single shot RAW, even though it looks a little more processed when pixel peeping.

There is clearly more noise in the single shot RAW (as you'd expect). However, bear in mind that the JPEG above shows the result of doing fairly heavy sharpening and no noise reduction whatsoever. With more balanced processing the noise is much less noticeable. Here's an example: https://drive.google.com/file/d/1PQKAcE-Cr-M6Uz-rcXTDt3OM0Ej...

Re: The limits of "computational photography"

#216

Post by fsloth »

leviathant wrote: post #133
fsloth wrote: post #109

Earlier quoted context omitted.

It composes the hdr as well?

The Canon T2i that I bought in 2010 sure did.

All the references I found just referred the auto-bracketing (I.e. shooting the the images with different exposure) but I can't find any mention of in-camera composition of the final hdr - all sources just tell you to use an external software for the HDR composition. I'm not doubting you but this sounds like an undermarketed obscure feature - can you find any references for this feature?

Re: The limits of "computational photography"

#217

Post by _aavaa_ »

buildbot wrote: post #214
astrange wrote: post #210

Earlier quoted context omitted.

I know what a DNG is. It's not a final delivery format; it's not compressed and I don't think eg gaming content pipelines are going to accept it for ingest either. (Also, macOS won't display them in HDR, but will display EXR files in HDR. Some trivia for you.)

-> It's not a final delivery format linear DNG? -> it's not compressed "Lossless and lossy compression (optional): DNG support optional lossless and (since version 1.4) also lossy compression.[36] The lossy compression losses are practically imperceptible in real world images" -> I don't think eg gaming content pipelines Why is this a goalpost even??? In what context? Photogrammetry? DNG works just fine.... Or the ac…

I actually now agree with them. I think they were simply doing a bad job explaining.

What I think they mean is that the iPhone camera app is the only one that takes an HDR photo of a scene a produces and HDR output image[0] that can be easily shared and viewed IN HDR on multiple devices.

I don't think that EXR is a particularly portable format (do phones even support viewing them in their native photo viewer/manager?) nor one with small file sizes.

The DNGs from Capture One or Lightroom have similar issues, they at least can be viewed on phones, but they do not show up as HDR images.

Other applications, e.g. Hugin, will produce and SDR image. It's based on an HDR image so it captures a wider dynamic range, but it does it through tone mapping back into a SDR image, rather than actually saving and showing the full dynamic range of the HDR image.

[0] I am not convinced that what the iPhone does with their heic images is really HDR, in the sense that the colors still seem to be stored in an SDR range.

Re: The limits of "computational photography"

#218

Post by Terretta »

whywhywhywhy wrote: post #72

Haven’t felt like the camera on my iPhone 13 is significantly better than the one on my iPhone 7 at all in terms of basic quality. My shots look about the same. As someone who upgrades every several years I’ve been wondering how people who upgrade every year and rave about the camera being better are even seeing at this point. (Stills only I’m talking about)

Telephoto and low light

Also, the camera, lenses, and sensors don't all update every year. Early on in Apple's tick-tock approach to design iteration, camera updates were the "s" models ("tock") in release cycle.

Now they seem to be just incrementing the number and you have to pay attention to what if any changes they make. This time they did 4x pixels and do pixel binning for regular shots and low light.

Re: The limits of "computational photography"

#219

Post by eru »

sebzim4500 wrote: post #190
eru wrote: post #43

Earlier quoted context omitted.

> as long as there is anything to key onto it's possible to remove the shake algorithmically Why the requirement? The phone already has accelerometers, doesn't it? In any case, less hake should still be easier for the phone to deal with. Those algorithms aren't flawless.

There's no way that the accelerators/gyrocscope would be accurate enough to remove the shake. According to google, the iphone gyroscope is accurate to within about 0.5 degrees, roughly two orders of magnitude away from being pixel accurate in a 1x zoom image.

Thanks for providing the numbers!

Re: The limits of "computational photography"

#220

Post by zeckalpha »

Tepix wrote: post #50
zeckalpha wrote: post #29

The inverse has been how wowed I am when a camera is better than my vision. Night mode and giant aperture ratio lenses both wow me. Mirrorless cameras may have been delayed if it weren't for the competition with phones. DSLRs were only around a few years before camera phones.

Lenses in general can make things larger than with normal vision, so why are you so surprised?

Not larger or smaller, I mean better in low light. Large aperture is very different from large focal length.
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