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The limits of "computational photography"

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Re: The limits of "computational photography"

#51

I love my big, heavy Nikon DSLR, and there's really no comparing the images it takes with the ones from my iPhone. Especially in "tricky" lighting situations they're not even in the same ballpark. That said, there can be just as much (or more) "computational photography" going on with a digital camera as there is with a modern phone, the difference is that cameras and processing software give control to the user, and…

I also love my big heavy Canon DSLR. Can’t quite describe why it gives me so much joy, but I keep it around me at all times. I just love taking photos.

The quality difference is also very obvious compared to my phone even though my camera is easily 8 years old.

Re: The limits of "computational photography"

#52

I love my big, heavy Nikon DSLR, and there's really no comparing the images it takes with the ones from my iPhone. Especially in "tricky" lighting situations they're not even in the same ballpark. That said, there can be just as much (or more) "computational photography" going on with a digital camera as there is with a modern phone, the difference is that cameras and processing software give control to the user, and…

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.

Re: The limits of "computational photography"

#53

Earlier quoted context omitted.

I didn't see any invented "new details" in the article's iPhone photos. Phones have small sensors and crap lenses, so they ramp up noise reduction and sharpness to make up for it. Turn up the ISO and max out the NR on the Fujifilm and the results would be nearly as bad.

I see invented texture and layering here: https://yager.io/comp/mi.jpeg

That seems just like edge sharpening.

Re: The limits of "computational photography"

#54

Earlier quoted context omitted.

> As far as I know, iPhone and Android aren't doing anything that isn't already done by digital cameras. It's the opposite, most digital cameras aren't doing enough compared to smartphones, which have minimum control and look very good at 2M pixels. A proper camera with default settings looks bland in the hands of an amateur (too little saturation) and handles dynamic range poorly (without bracketing or post-processi…

I don't buy it. Which cameras have worse "Auto" settings than a phone? I have two Fujifilms, a Panasonic, and a Nikon, and they all take better photos on "Auto" than my iPhone or any of my friends' Androids. And who buys a camera in this day and age but doesn't want to play with the settings? Point and shoot users stick with their phones now.

It's not about better or worse, it's about trade offs. At small social media sizes pictures will look better from a phone than from an enthusiast camera.

Sharpening is a destructive process and the appropriate amount depends on how and what size you are using the image. It can also be easily applied anytime later. So enthusiast camera apply minimal sharpening and look under sharpened at small sizes, and phone cameras apply heavy sharpening but have artefacts if you zoom into them.

Same with saturation and 'ai' tricks like skin smoothing: users of enthusiast cameras often have different preferences.

Re: The limits of "computational photography"

#55

> the relevant metric is what I call “photographic bandwidth” - the information-theoretic limit on the amount of optical data that can be absorbed by the camera under given photographic conditions (ambient light, exposure time, etc.). You mean, "resolution"?

'resolution' is usually used just to mean the number of pixels: nothing about how much ligh they capture or what sort of lens and processing.

Re: The limits of "computational photography"

#56

I always shoot in Raw (using the Lightroom iPhone App) to make sure that this kind of defects never occur. Noise is generally preferable and acceptable that the disaster trail left by denoising et al. At least you can do it yourself in a way that pleases you instead of having a ruined photograph.

With the pixel6 (and most android phones) you can set it up to do both. So you have the "nice" version generated by the phone and a dng raw file to work with. I have that set up along with syncthing to deliver the raw photos to my laptop (pro tip, this is super handy).

The new iphone and the pixel6 both use the same trick where they have a 50 megapixel sensor (probably the same and likely a Sony sensor) that produces 12.5 megapixel raw photos with four pixels combined information. So the dng I get from my phone has already had some processing done to it but not a lot. Also worth noting that both phones have multiple lenses with different focal lengths and sensors. So, it matters a lot which one you use. You'd control this via the camera app typically with its different modes and zoom levels. I'm not sure if it uses exposures from all sensors to calculate a better raw but that would not surprise me.

In terms of noise, the image quality is actually very good. I've done some night time photography with both the pixel6 and my Fuji XT-30, which is an entry level mirror less camera. The Fuji has better dynamic range and it shows in the dark. But the noise levels are actually pretty good for a phone camera. Very usable results with some simple post processing. Especially compared to my previous Android phone (a Nokia 7 plus) which was noisy even in day light. Mostly doing raw edits is not worth doing that but it's nice to have the option. The phone does a decent job of processing and mostly gets it right when it comes to tone mapping and noise reduction. When it matters, I prefer the Fuji. But sometimes the phone is all you have and you just take a quick photo and it's fine.

A high end full frame camera will get you more and better pixels and more detail. Even an older entry level dslr will generally run circles around smart phone sensors. And that's just the sensor and camera. The real reason to use these is the wide variety of lenses and level of control over the optics that those provide. In phone bokeh is a nice gimmick. But it's a fake effect compared to a nice quality lens. Likewise you can't really fake the look you get with a good portrait lens (the effect that things in the background seem bigger). Phone lenses have a fixed focal range and generally not that much aperture range. There's a reason people pay large amounts of money to own good lenses. They are really nice to use and deliver a great photo without a lot of digital trickery. And they are optimized for different types of photography. There is no one size fits all lens for all photography.

Re: The limits of "computational photography"

#57
post #35

Earlier quoted context omitted.

I'm not exactly sure what you're asking for here. In my experience (and as seen in the article) the image processing in most digital cameras will already blow an iPhone out of the water. As far as I know, iPhone and Android aren't doing anything that isn't already done by digital cameras. They ramp up the settings on things like noise reduction and sharpness to balance out their tiny sensors, but it's more or less th…

I think you’re missing what makes iPhone photos look so good; they do much more than just ramping up the sliders on sharpness. When you take sunlit panoramas for instance, the iPhone will auto bracket and perform hdr treatment, it’s fantastic : you can see both the ground and the blue sky and the clouds. You can’t do that easily with a dslr, certainly not like a phone is doing right now, which is integrating the last…

> You can’t do that easily with a dslr, certainly not like a phone is doing right now, which is integrating the last x frames and modulating the digital shutter to capture multiple exposures.

Standalone cameras have been doing this for at least a decade. The same is true for nighttime exposures. That's not to say that the iPhone doesn't do it better, maybe it does, it certainly can throw more processing power at it.

https://www.imaging-resource.com/PRODS/sony-a3000/sony-a3000...

Re: The limits of "computational photography"

#58

I would like to see computational photography applied to raw images from DSLRs and MILCs with APS-C and larger sensors. Perhaps Canon, Nikon, Sony, and Fujifilm could have built-in options in their cameras for ‘social media mode’, with a modicum of noise reduction (honestly unnecessary at ISOs lower than about 1600 for modern cameras), but drastically improved HDR and white balance. Many of these cameras are able to…

[deleted]

Re: The limits of "computational photography"

#59

I love my big, heavy Nikon DSLR, and there's really no comparing the images it takes with the ones from my iPhone. Especially in "tricky" lighting situations they're not even in the same ballpark. That said, there can be just as much (or more) "computational photography" going on with a digital camera as there is with a modern phone, the difference is that cameras and processing software give control to the user, and…

"Real" cameras do a lot of postprocessing too, but it's generally oriented at producing faithful results. They might remove unambiguous and correctable issues such as vignetting or lens distortion, but they don't cross the line of inventing new details to make the photo look good. Computational photography techniques on smartphones, on the other hand, were always designed around squishy "user perception" goals to mak…

At the end of the day you're always "inventing new details" to turn sensor data into an image. Most algorithms involve edge detection and predicting color correlations, and you'll also run into cases where false details are added and reality is changed to fit the priors.

One can find pathological cases for traditional cameras too - moire is a common problem, Fuji X-Trans sensors historically had a watercolor/worms effect particularly in greenery, etc.

Re: The limits of "computational photography"

#60
post #46

I would like to see computational photography applied to raw images from DSLRs and MILCs with APS-C and larger sensors. Perhaps Canon, Nikon, Sony, and Fujifilm could have built-in options in their cameras for ‘social media mode’, with a modicum of noise reduction (honestly unnecessary at ISOs lower than about 1600 for modern cameras), but drastically improved HDR and white balance. Many of these cameras are able to…

They already are. However, most photographers do not appreciate this type of distortion being applied to their images. At a glance, my samsung note 22 ultra takes better picture than my nikon d7500. At a glance. However, as soon as you want to actually DO anything to it, like, view it in any real detail, or on anything but a tiny screen, reality returns.. While the phone is absolutely fantastic for a quick snapshot,…

This! My close to 10 year old DSLR still outperforms the latest and greatest on any phone for this reason.
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