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What an unprocessed photo looks like

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Re: What an unprocessed photo looks like

#311

Post by wolvoleo »

isoprophlex wrote: post #209
delecti wrote: post #23

Earlier quoted context omitted.

I have a related anecdote. When I worked at Amazon on the Kindle Special Offers team (ads on your eink Kindle while it was sleeping), the first implementation of auto-generated ads was by someone who didn't know that properly converting RGB to grayscale was a smidge more complicated than just averaging the RGB channels. So for ~6 months in 2015ish, you may have seen a bunch of ads that looked pretty rough. I think I…

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)

Re: What an unprocessed photo looks like

#312

Post by jnovek »

acomjean wrote: post #169
kccqzy wrote: post #74

Earlier quoted context omitted.

I remember using some photo editing software (Aperture I think) that would allow you to customize the different coefficients and there were even presets that give different names to different coefficients. Ultimately you can pick any coefficients you want, and only your eyes can judge how nice they are.

>Ultimately you can pick any coefficients you want, and only your eyes can judge how nice they are. I went to a photoshop conference. There was a session on converting color to black and white. Basically at the end the presenter said you try a bunch of ways and pick the one that looks best. (people there were really looking for the “one true way”) I shot a lot of black and white film in college for our paper. One of…

This is actually a real bother to me with digital — I can never get a digital photo to follow the same B&W sensitivity curve as I had with film so I can never digitally reproduce what I “saw” when I took the photo.

Re: What an unprocessed photo looks like

#313

Post by seba_dos1 »

boltzmann-brain wrote: post #157
shagie wrote: post #101

Earlier quoted context omitted.

> A fun tangent on the "green cast" mentioned in the post: the reason the Bayer pattern is RGGB (50% green) isn't just about color balance, but spatial resolution. The human eye is most sensitive to green light, so that channel effectively carries the majority of the luminance (brightness/detail) data. From the classic file format "ppm" (portable pixel map) the ppm to pgm (portable grayscale map) man page: https://li…

Funnily enough that's not the only mistake he made in that article. His final image is noticeably different from the camera's output image because he rescaled the values in the first step. That's why the dark areas look so crushed, eg around the firewood carrier on the lower left or around the cat, and similarly with highlights, e.g. the specular highlights on the ornaments. After that, the next most important proble…

You do need to rescale the values as the first step, but not exactly the described way (you need to subtract the data pedestal in order to get linear values).

Re: What an unprocessed photo looks like

#314

Post by naths88 »

Fed it to Gemini 3 pro and got this remark :

The "Squid" Note: You might notice a weird hidden text at the bottom of that webpage about a squid—ignore that, it's a "prompt injection" joke for AI bots! The relevant content is purely the image processing.

Re: What an unprocessed photo looks like

#315

Post by trinix912 »

vbezhenar wrote: post #282
trinix912 wrote: post #238

Earlier quoted context omitted.

Except it seems to be going in the opposite direction, every phone I've upgraded (various Androids and iPhones) seemed to have more smoothing than the one I'd had before. My iPhone 16 night photos look like borderline generative AI and there's no way to turn that off! I was honestly happier with the technically inferior iPhone 5 camera, the photos at least didn't look fake.

If you can get raw image data from the sensor, then there will be apps to produce images without AI processing. Ordinary people love AI enhancements, so built-in apps are optimised for this approach, but as long as underlying data is accessible, there will be third-party apps that you can use.

That's a big IF. There's ProRaw but for that you need an iPhone Pro, some Androids have RAW too but it's huge and lacks even the most basic processing resulting in photos that look like one of the non-final steps in the post.

Third party apps are hit or miss, you pay for one only to figure out it doesn't actually get the raw output on your model and so on.

There's very little excuse for phone manufacturers to not put a toggle to disable excessive post-processing. Even iOS had an HDR toggle but they've removed it since.

Re: What an unprocessed photo looks like

#316

Post by macintux »

acomjean wrote: post #175
kdazzle wrote: post #163

Earlier quoted context omitted.

Exactly - film photographers heavily process(ed) their images from the film processing through to the print. Ansel Adams wrote a few books on the topic and they’re great reads. And different films and photo papers can have totally different looks, defined by the chemistry of the manufacturer and however _they_ want things to look.

Excepting slide photos. No real adjustment once taken (a more difficult medium than negative film which you can adjust a little when printing) You’re right about Ansel Adams. He “dodged and burned” extensively (lightened and darkened areas when printing.) Photoshop kept the dodge and burn names on some tools for a while. https://m.youtube.com/watch?v=IoCtni-WWVs When we printed for our college paper we had a dial tha…

I found one way to "adjust" slide photos: I accidentally processed a (color) roll of mine using C-41. The result was surprisingly not terrible.

Re: What an unprocessed photo looks like

#317

Post by cellular »

seba_dos1 wrote: post #85
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.

The article doesn't even go anywhere near what you need to do in order to get an acceptable output. It only shows the absolute basics. If you apply only those to a photo from a phone camera, it will be massively distorted (the effect is smaller, but still present on big cameras).

When i worked on image pipeline the images were circular and had to be warped to square. Also the edges of the circular image were darker than the middle, and needed to be brightened.

Re: What an unprocessed photo looks like

#318

Post by seba_dos1 »

frumiousirc wrote: post #277
devsda wrote: post #254

Earlier quoted context omitted.

Is it related to the fact that monkeys/humans evolved around dense green forests ?

Well, plants and eyes long predate apes. Water is most transparent in the middle of the "visible" spectrum (green). It absorbs red and scatters blue. The atmosphere has a lot of water as does, of course, the ocean which was the birth place of plants and eyeballs. It would be natural for both plants and eyes to evolve to exploit the fact that there is a green notch in the water transparency curve. Edit: after scrollin…

Eyes aren't all equal. Our trichromacy is fairly rare in the world of animals.

Re: What an unprocessed photo looks like

#319

Post by shagie »

reactordev wrote: post #306
zinekeller wrote: post #290

Earlier quoted context omitted.

(this is just a rant) Honestly, the weird 16-239 (on 8-bit) color range and 60000/1001 fps limitations stem from the original NTSC standard, which considering both the Japanese NTSC adaptation and European standards do not have is rather frustating nowadays. Both the HDVS and HD-MAC standards define it in precise ways (exactly 60 fps for HDVS and 0-255 color range for HD-MAC*) but America being America... * I know th…

Ya’ll are a gold mine. Thank you. I only knew it from my forays into computer graphics and making things look right on (now older) LCD TV’s. I pulled it from some old academia papers about why you can’t just max(uv.rgb) to do greyscale nor can you do float val = uv.r This further gets funky when we have BGR vs RGB and have to swivel the bytes beforehand. Thanks for adding clarity and history to where those weights ca…

> People don’t realize how many man hours went into those early decisions.

In my "trying to hunt down the earliest reference for the coefficients" I came across "Television standards and practice; selected papers from the Proceedings of the National television system committee and its panels" at https://archive.org/details/televisionstanda00natirich/mode/... which you may enjoy. The "problem" in trying to find the NTSC color values is that the collection of papers is from 1943... and color TV didn't become available until the 50s (there is some mention of color but I couldn't find it) - most of the questions of color are phrased with "should".

Re: What an unprocessed photo looks like

#320

Post by seba_dos1 »

matsemann wrote: post #278
f1shy wrote: post #202

Earlier quoted context omitted.

> The human eye is most sensitive to green light, This argument is very confusing: if is most sensitive, less intensity/area should be necessary, not more.

Yeah, was thinking the same. If we're more sensitive, why do we need double sensors? Just have 1:1:1, and we would anyways see more of the green? Won't it be too much if we do 1:2:1, when we're already more perceptible to green?

With 1:1:1 the matrix isn't square, and if you have to double one of the channels for practical purposes then the green one is the obvious pick as it's the most beneficial in increasing the image quality cause it's increasing the spatial resolution where our eyes can actually notice it.

Grab a random photo and blur its blue channel out a bit. You probably won't notice much difference aside of some slight discoloration. Then try the same with the green channel.

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