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What an unprocessed photo looks like

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Re: What an unprocessed photo looks like

#411

Post by names_are_hard »

eloisius wrote: post #388
Edman274 wrote: post #360

Earlier quoted context omitted.

Is it fair to recognize that there is a category difference between the processing that happens by default on every cell phone camera today, and the time and labor intensive processing performed by professionals in the time of film? What's happening today is like if you took your film to a developer and then the negatives came back with someone having airbrushed out the wrinkles and evened out skin tones. I think tha…

It’s fair to recognize. Personally I do not like the aesthetic decisions that Apple makes, so if I’m taking pictures on my phone I use camera apps that’s give me more control (Halide, Leica Lux). I also have reservations about cloning away power lines or using AI in-painting. But to your example, if you got your film scanned or printed, in all likelihood someone did go in and change some stuff. Color correction and t…

I would argue that there's a qualitative difference between processing that aims to get the image to the point where it's a closer rendition of how the human eye would have perceived the subject (the stuff described in TFA) vs processing that explicitly tries to make the image further from the in-person experience (removing power lines, people from the background, etc)

Re: What an unprocessed photo looks like

#412

Post by [deleted] »

liampulles wrote: post #373
kuschku wrote: post #298

Earlier quoted context omitted.

> Small neural networks I believe are the current state of the art (e.g. train to reverse a 16x16 color filter pattern for the given camera). What is currently in use by modern digital cameras is all trade secret stuff. Considering you usually shoot RAW, and debayer and process in post, the camera hasn't done any of that. It's only smartphones that might be doing internal AI Debayering, but they're already hallucinat…

Sure - if you don't want to do demosaicing on the camera, that's fine. It doesn't mean there is not an algorithm there as an option. If you care about trying to get an image that is as accurate as possible to the scene, then it is well within your interest to use a Convolutional Neural Network based algorithm, since these are amongst the highest performing in terms of measured PSNR (which is what nearly all demosaici…

[deleted]

Re: What an unprocessed photo looks like

#413

Post by kuschku »

liampulles wrote: post #373
kuschku wrote: post #298

Earlier quoted context omitted.

> Small neural networks I believe are the current state of the art (e.g. train to reverse a 16x16 color filter pattern for the given camera). What is currently in use by modern digital cameras is all trade secret stuff. Considering you usually shoot RAW, and debayer and process in post, the camera hasn't done any of that. It's only smartphones that might be doing internal AI Debayering, but they're already hallucinat…

Sure - if you don't want to do demosaicing on the camera, that's fine. It doesn't mean there is not an algorithm there as an option. If you care about trying to get an image that is as accurate as possible to the scene, then it is well within your interest to use a Convolutional Neural Network based algorithm, since these are amongst the highest performing in terms of measured PSNR (which is what nearly all demosaici…

At least in broadcast/cinema, no one uses CNN for debayering, because why would you?

In cinema, you just use a 6K sensor and use conventional debayering for a perfect 4K image. Even the $2000 Sony FX-30 ships with that feature nowadays. Combined with a good optical low pass filter, that'll also avoid any and all moiré noise.

In broadcast, if you worry about moiré noise or debayering quality, you just buy a Sony Z750 with a three-chip prism design, which avoids the problem entirely by just having three separate full-resolution sensors.

Re: What an unprocessed photo looks like

#414

Post by nomel »

card_zero wrote: post #79
nomel wrote: post #67

Earlier quoted context omitted.

And this is important because our perception is more sensitive to luminance changes than color, and with our eyes being most sensitive to green, luminance is also. So, higher perceived spatial resolution by using more green [1]. This is also why JPG has lower resolution red and green channels, and why modern OLED usually use a pentile display, with only green being at full resolutio [2]. [1] https://en.wikipedia.org/…

Funny that subpixels and camera sensors aren't using the same layouts.

It would only be relevant if viewing the image at one-to-one resolution, which is extremely rare.

Re: What an unprocessed photo looks like

#415

Post by strogonoff »

fulafel wrote: post #225
strogonoff wrote: post #62

An unprocessed photo does not “look”. It is RGGB pixel values that far exceed any display media in dynamic range. Fitting it into the tiny dynamic range of screens by thrusting throwing away data strategically (inventing perceptual the neutral grey point, etc.) is what actually makes sense of them, and what is the creative task.

In the article adjusting for the range makes quite a small difference compared to the other steps.

When talking about range I mean not naively remapping it to fit display media, but compressing it to fill the range of the media in a way that achieves the desired look. (Accounting for non-linearity of colour vision is part of that mentioned in the article.)

Re: What an unprocessed photo looks like

#416

Post by strogonoff »

lnenad wrote: post #265
jibal wrote: post #158

Earlier quoted context omitted.

Right. the statement "Here’s a photo of a Christmas tree, as my camera’s sensor sees it" is incoherent.

Don't you think you're being a bit too pedantic? Nothing really "sees". Eyes also do gather light and the brain analyzes the signals. We've invented a word for it but the word is a high level abstraction that could easily be applied to a camera sensor as well.

I am very much on the triggered side when people say things like “this is how my camera sees it”, because it’s never what they show. What sensor sees is numbers that without interpretation by you, the human, and/or automated software are meaningless.

What people show when they say “this is how my camera sees it” is always “this is how I see it”, or more more specifically “this is how I want you to see it”—as the interpretation of that raw data is a critical part—and I think it’s not very pedantic to point it out.

Re: What an unprocessed photo looks like

#417

Post by account42 »

wolvoleo wrote: post #311
isoprophlex wrote: post #209

Earlier quoted context omitted.

I wouldn't worry about it too much, looking at ads is always a shitty experience. Correctly grayscaled or not.

True, though in the case of the Kindle they're not really intrusive (only appearing when it's off) and the price to remove them is pretty reasonable ($10 to remove them forever IIRC). As far as ads go that's not bad IMO)

Sure, and piss doesn't taste quite as bad as shit yet I still don't want it in my food.

Re: What an unprocessed photo looks like

#418

Post by account42 »

15155 wrote: post #386
qubitcoder wrote: post #383

Earlier quoted context omitted.

To be clear, they default to JPEG for the image preview on the monitor (LCD screen). Whenever viewing an image on a professional camera, you’re always seeing the resulting JPEG image. The underlying data is always captured as a RAW file, and only discarded if you’ve configured the camera to only store the JPEG image (discarding the original RAW file after processing).

> Whenever viewing an image on a professional camera Viewing any preview image on any camera implies a debayered version: who says is it JPEG-encoded - why would it need to be? Every time I browse my SD card full of persisted RAWs, is the camera unnecessarily converting to JPEG just to convert it back to bitmap display data? > The underlying data is always captured as a RAW file, and only discarded if you’ve configur…

The cameras typically store a camera display sized preview JPEG in the raw files.
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