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What an unprocessed photo looks like

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Re: What an unprocessed photo looks like

#221

Post by tobyhinloopen »

krackers wrote: post #4

>if the linear data is displayed directly, it will appear much darker then it should be. This seems more a limitation of monitors. If you had very large bit depth, couldn't you just display images in linear light without gamma correction.

The problem with their example is that you can display linear image data just fine, just not with JPEG. Mapping linear data to 255 RGB that expects the gamma-corrected values is just wrong. They could have used an image format that supports linear data, like JPEG-XL, AVIF or HEIC. No conversion to 0-255 required, just throw in the data as-is.

Re: What an unprocessed photo looks like

#223

Post by lefra »

ssl-3 wrote: post #161
BenjiWiebe wrote: post #134

Earlier quoted context omitted.

Wouldn't be a genuine version of what my eyes would've seen, had I been the one looking instead of the camera. I can't see infrared.

Perhaps interestingly, many/most digital cameras are sensitive to IR and can record, for example, the LEDs of an infrared TV remote. But they don't see it as IR. Instead, this infrared information just kind of irrevocably leaks into the RGB channels that we do perceive. With the unmodified camera on my Samsung phone, IR shows up kind of purple-ish. Which is... well... it's fake. Making invisible IR into visible purpl…

Silicon sensors (which is what you'll get in all visible-light cameras as far as I know) are all very sensitive to near-IR. Their peak sensitivity is around 900nm. The difference between cameras that can see or not see IR is the quality of their anti-IR filter.

Your Samsung phone probably has the green filter of its bayer matrix that blocks IR better than the blue and red ones.

Here's a random spectral sensitivity for a silicon sensor:

https://encrypted-tbn0.gstatic.com/images?q=tbn:ANd9GcRkffHX...

Re: What an unprocessed photo looks like

#224

Post by liampulles »

userbinator wrote: post #5

I think everyone agrees that dynamic range compression and de-Bayering (for sensors which are colour-filtered) are necessary for digital photography, but at the other end of the spectrum is "use AI to recognise objects and hallucinate what they 'should' look like" --- and despite how everyone would probably say that isn't a real photo anymore, it seems manufacturers are pushing strongly in that direction, raising iss…

ML demosaicing algorithms (e.g. convolutional neural networks) are the state of the art for reversing camera color filters, and this was true back when I did my post-grad studies on the subject almost 10 years ago, not to mention all the other stages of the post-processing stack. So one will have to wrestle with the fact that some form of "AI" has been part of digital images for a while now.

I mean to some degree, human perception is a hallucination of reality. It is well known by magicians that if you know the small region of space that a person is focusing on, then you can totally change other areas of the scene without the person noticing.

Re: What an unprocessed photo looks like

#225

Post by fulafel »

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.

Re: What an unprocessed photo looks like

#226

Post by littlestymaar »

henrebotha wrote: post #208
dahart wrote: post #132

Earlier quoted context omitted.

> does applying the same transfer function to each pixel (of a given colour anyway) count as “processing”? This is interesting to think about, at least for us photo nerds. ;) I honestly think there are multiple right answers, but I have a specific one that I prefer. Applying the same transfer function to all pixels corresponds pretty tightly to film & paper exposure in analog photography. So one reasonable followup q…

It's like food: Virtually all food is "processed food" because all food requires some kind of process before you can eat it. Perhaps that process is "picking the fruit from the tree", or "peeling". But it's all processed in one way or another.

Hence the qualifier in “ultra-processed food”

Re: What an unprocessed photo looks like

#227

Post by Toutouxc »

card_zero wrote: post #43
nospice wrote: post #8

Earlier quoted context omitted.

> A better discriminator might be global edits vs local edits, Even that isn't all that clear-cut. Is noise removal a local edit? It only touches some pixels, but obviously, that's a silly take. Is automated dust removal still global? The same idea, just a bit more selective. If we let it slide, what about automated skin blemish removal? Depth map + relighting, de-hazing, or fake bokeh? I think that modern image proc…

What's this, special pleading for doctored photos? The only process in the article that involves nearby pixels is to combine R G and B (and other G) into one screen pixel. (In principle these could be mapped to subpixels.) Everything fancier than that can be reasonably called some fake cosmetic bullshit.

In that case you can't reasonably do digital photography without "fake cosmetic bullshit" and no current digital camera will output anything even remotely close to no fake cosmetic bullshit.

Re: What an unprocessed photo looks like

#228

Post by card_zero »

Toutouxc wrote: post #227
card_zero wrote: post #43

Earlier quoted context omitted.

What's this, special pleading for doctored photos? The only process in the article that involves nearby pixels is to combine R G and B (and other G) into one screen pixel. (In principle these could be mapped to subpixels.) Everything fancier than that can be reasonably called some fake cosmetic bullshit.

In that case you can't reasonably do digital photography without "fake cosmetic bullshit" and no current digital camera will output anything even remotely close to no fake cosmetic bullshit.

That sounds likely. I wonder what specific filters can't be turned off, though. I think you can usually turn off sharpening. Maybe noise removal is built-in somehow (I think somebody else said it's in the sensor).

Re: What an unprocessed photo looks like

#230

Post by card_zero »

tpmoney wrote: post #192
sho_hn wrote: post #59

Earlier quoted context omitted.

Pretending that "these two things are the same, actually" when in fact no, you can seperately name and describe them quite clearly, is a favorite pastime of vacuous content on the internet. Artists, who use these tools with clear vision and intent to achieve specific goals, strangely never have this problem.

But that was the point the OP was making. Not that you couldn’t differentiate between white balance correction and generative fill, but rather that the intent of the change matters for determining if an image is “fake”. For example, I took a picture of my dog at the dog park the other day. I didn’t notice when framing the picture but on review at home, right smack in the middle of the lower 3rd of the photo and conve…

I don't know, removing the turd from that picture reminds me of when Stalin had the head of the NKVD (deceased) removed from photos after the purge. It sounds like the turd was probably the focus of all your dog's attention and interest at the time, and editing it out has created a misleading situation in a way that would be outrageous if I was a dog and capable of outrage.
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