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What an unprocessed photo looks like

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Re: What an unprocessed photo looks like

#201

Post by integralid »

barishnamazov wrote: post #7

I love posts that peel back the abstraction layer of "images." It really highlights that modern photography is just signal processing with better marketing. 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 t…

And this is just what happens for a single frame. It doesn't even touch computational photography[1].

[1] https://dpreview.com/articles/9828658229/computational-photo...

Re: What an unprocessed photo looks like

#202

Post by f1shy »

barishnamazov wrote: post #7

I love posts that peel back the abstraction layer of "images." It really highlights that modern photography is just signal processing with better marketing. 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 t…

> 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.

Re: What an unprocessed photo looks like

#203

Post by doubletwoyou »

mwambua wrote: post #182
barishnamazov wrote: post #7

I love posts that peel back the abstraction layer of "images." It really highlights that modern photography is just signal processing with better marketing. 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 t…

> The human eye is most sensitive to green light, so that channel effectively carries the majority of the luminance (brightness/detail) data How does this affect luminance perception for deuteranopes? (Since their color blindness is caused by a deficiency of the cones that detect green wavelengths)

The cones are the colour sensitive portion of the retina, but only make up a small percent of all the light detecting cells. The rods (more or less the brightness detecting cells) would still function in a deuteranopic person, so their luminance perception would basically be unaffected.

Also there’s something to be said about the fact that the eye is a squishy analog device, and so even if the medium wavelengths cones are deficient, long wavelength cones (red-ish) have overlap in their light sensitivities along with medium cones so…

Re: What an unprocessed photo looks like

#204

Post by Uncorrelated »

seba_dos1 wrote: post #77
to11mtm wrote: post #58

Earlier quoted context omitted.

JPEG with OOC processing is different from JPEG OOPC (out-of-phone-camera) processing. Thank Samsung for forcing the need to differentiate.

I wrote the raw Bayer to JPEG pipeline used by the phone I write this comment on. The choices on how to interpret the data are mine. Can I tweak these afterwards? :)

I found the article you wrote on processing Librem 5 photos:

https://puri.sm/posts/librem-5-photo-processing-tutorial/

Which is a pleasant read, and I like the pictures. Has the Librem 5's automatic JPEG output improved since you wrote the post about photography in Croatia (https://dosowisko.net/l5/photos/)?

Re: What an unprocessed photo looks like

#205

Post by 71bw »

astrange wrote: post #191
NiloCK wrote: post #142

You may know that intermittent rashes are always invisible in the presence of medical credentials. Years ago I became suspicious of my Samsung Android device when I couldn't produce a reliable likeness of an allergy induced rash. No matter how I lit things, the photos were always "nicer" than what my eyes recorded live. The incentives here are clear enough - people will prefer a phone whose camera gives them an impre…

iOS added a camera mode for medical photos that extra doesn't do that. https://developer.apple.com/videos/play/wwdc2024/10162/

This is VERY interesting and I am glad you posted this, as it is my first time coming across this.

Re: What an unprocessed photo looks like

#206

Post by volemo »

mwambua wrote: post #182
barishnamazov wrote: post #7

I love posts that peel back the abstraction layer of "images." It really highlights that modern photography is just signal processing with better marketing. 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 t…

> The human eye is most sensitive to green light, so that channel effectively carries the majority of the luminance (brightness/detail) data How does this affect luminance perception for deuteranopes? (Since their color blindness is caused by a deficiency of the cones that detect green wavelengths)

It’s not that their M-cones (middle, i.e. green) don’t work at all, their M-cones responsivity curve is just shifted to be less distinguishable from their L-cones curve, so they effectively have double (or more) the “red sensors”.

Re: What an unprocessed photo looks like

#207

Post by ozim »

sho_hn wrote: post #54
bstsb wrote: post #42

Earlier quoted context omitted.

hey, not accusing you of anything (bad assumptions don't lead to a conducive conversation) but did you use AI to write or assist with this comment? this is totally out of my own self-interest, no problems with its content

Upon inspection, the author's personal website used em dashes in 2023. I hope this helped with your witch hunt. I'm imagining a sort of Logan's Run-like scifi setup where only people with a documented em dash before November 30, 2022, i.e. D(ash)-day, are left with permission to write.

I started to use — dash so that algos skip my writing thinking they were AI generated.

Re: What an unprocessed photo looks like

#208

Post by henrebotha »

dahart wrote: post #132
MarkusWandel wrote: post #94

But does applying the same transfer function to each pixel (of a given colour anyway) count as "processing"? What bothers me as an old-school photographer is this. When you really pushed it with film (e.g. overprocess 400ISO B&W film to 1600 ISO and even then maybe underexpose at the enlargement step) you got nasty grain. But that was uniform "noise" all over the picture. Nowadays, noise reduction is impressive, but…

> 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.

Re: What an unprocessed photo looks like

#209

Post by isoprophlex »

delecti wrote: post #23
barishnamazov wrote: post #7

I love posts that peel back the abstraction layer of "images." It really highlights that modern photography is just signal processing with better marketing. 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 t…

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.

Re: What an unprocessed photo looks like

#210

Post by viraptor »

integralid wrote: post #194
tpmoney wrote: post #184

Earlier quoted context omitted.

I didn’t read the article as implying that the final image the author arrived at was “unprocessed”. The point seemed to be that the first image was “unprocessed” but that the “unprocessed” image isn’t useful as a “photo”. You only get a proper “picture” Of something after you do quite a bit of processing.

Definitely what the author means: >There’s nothing that happens when you adjust the contrast or white balance in editing software that the camera hasn’t done under the hood. The edited image isn’t “faker” then the original: they are different renditions of the same data.

That's not how I read it. As in, this is an incidental comment. But the unprocessed version is the raw values from the sensors visible in the first picture, the processed are both the camera photo and his attempt at the end.
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