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What an unprocessed photo looks like

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Re: What an unprocessed photo looks like

#321

Post by skinwill »

liampulles wrote: post #253
NooneAtAll3 wrote: post #234

Earlier quoted context omitted.

> we are most sensitive to red light > green does indeed overwhelmingly contribute to perceptual luminance so... if luminance contribution is different from "sensitivity" to you - what do you imply by sensitivity?

Upon further reading, I think I am wrong here. My confusion was that I read that over 60% of the cones in ones eye are "red" cones (which is a bad generalization), and there is more nuance here. Given equal power red, blue, or green light hitting our eyes, humans tend to rate green "brighter" in pairwise comparative surveys. That is why it is predominant in a perceptual luminance calculation converting from RGB. Thou…

This is way over simplifying here but I always understood it as: our eyes can see red with very little power needed. But our eyes can differentiate more detail with green.

Re: What an unprocessed photo looks like

#322

Post by galleywest200 »

Toutouxc wrote: post #236
Dylan16807 wrote: post #222

Earlier quoted context omitted.

They probably do know what they're asking for, they're just using an ambiguous word.

My mirrorless camera shoots in RAW. When someone asks me if a certain photo was “edited”, I honestly don’t know what to answer. The files went through a RAW development suite that applied a bewildering amount of maths to transform them into a sRGB image. Some of the maths had sliders attached to it and I have moved some of the sliders, but their default positions were just what the software thought was appropriate. T…

I just tell people it was “color corrected” and “color graded” by me if I do any development in a program like Affinity. I never let “AI” tools touch my photos though.

Re: What an unprocessed photo looks like

#323

Post by JKCalhoun »

reactordev wrote: post #52
barishnamazov wrote: post #36

Earlier quoted context omitted.

I don't think Kindle ads were available in my region in 2015 because I don't remember seeing these back then, but you're a lucky one to fix this classic mistake :-) I remember trying out some of the home-made methods while I was implementing a creative work section for a school assignment. It’s surprising how "flat" the basic average looks until you actually respect the coefficients (usually some flavor of 0.21R + 0.…

If you really want that old school NTSC look: 0.3R + 0.59G + 0.11B This is the coefficients I use regularly.

Yep, used in the early MacOS color picker as well when displaying greyscale from RGB values. The three weights (which of course add to 1.0) clearly show a preference for the green channel for luminosity (as was discussed in the article).

Re: What an unprocessed photo looks like

#324

Post by heckelson »

shiandow wrote: post #248
thousand_nights wrote: post #63

Earlier quoted context omitted.

the bayer pattern is one of those things that makes me irrationally angry, in the true sense, based on my ignorance of the subject what's so special about green? oh so just because our eyes are more sensitive to green we should dedicate double the area to green in camera sensors? i mean, probably yes. but still. (⩺_⩹)

You think that's bad? Imagine finding out that all video still encodes colour at half resolution simply because that is how analog tv worked.

Isn't it the other way round? We did and still do chroma subsampling _because_ we don't see that much of a difference?

Re: What an unprocessed photo looks like

#325

Post by seba_dos1 »

shiandow wrote: post #248
thousand_nights wrote: post #63

Earlier quoted context omitted.

the bayer pattern is one of those things that makes me irrationally angry, in the true sense, based on my ignorance of the subject what's so special about green? oh so just because our eyes are more sensitive to green we should dedicate double the area to green in camera sensors? i mean, probably yes. but still. (⩺_⩹)

You think that's bad? Imagine finding out that all video still encodes colour at half resolution simply because that is how analog tv worked.

I don't think that's correct. It's not "all video" - you can easily encode video without chroma subsampling - and it's not because this is how analog TV worked, but rather for the same reason why analog TV worked this way, which is the fact that it lets you encode significantly less data with barely noticeable quality loss. JPEGs do the same thing.

Re: What an unprocessed photo looks like

#326

Post by the_af »

userbinator wrote: post #17
stavros wrote: post #6

Earlier quoted context omitted.

One thing I've learned while dabbling in photography is that there are no "fake" images, because there are no "real" images. Everything is an interpretation of the data that the camera has to do, making a thousand choices along the way, as this post beautifully demonstrates. A better discriminator might be global edits vs local edits, with local edits being things like retouching specific parts of the image to make d…

Everything is an interpretation of the data that the camera has to do What about this? https://news.ycombinator.com/item?id=35107601

Wow.

From one of the comments there:

> When people take a picture on the moon, they want a cool looking picture of the moon, and every time I have take a picture of the moon, on what is a couple of year old phone which had the best camera set up at the time, it looks awful, because the dynamic range and zoom level required is just not at all what smart phones are good at.

> Hence they solved the problem and gave you your picture of the moon. Which is what you wanted, not a scientifically accurate representation of the light being hit by the camera sensor. We had that, it is called 2010.

Where does one draw the line though? This is a kind of lying, regardless of the whole discussion about filters and photos always being an interpretation of raw sensor data and whatnot.

Again, where does one draw the line? The person taking a snapshot of the moon expects a correlation between the data captured by the sensor and whatever they end up showing their friends. What if the camera only acknowledged "ok, this user is trying to photograph the moon" and replaced ALL of the sensor data with a library image of the moon it has stored in its memory? Would this be authentic or fake? It's certainly A photo of the moon, just not a photo taken with the current camera. But the user believes it's taken with their camera.

I think this is lying.

Re: What an unprocessed photo looks like

#328

Post by the_af »

stavros wrote: post #6
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…

One thing I've learned while dabbling in photography is that there are no "fake" images, because there are no "real" images. Everything is an interpretation of the data that the camera has to do, making a thousand choices along the way, as this post beautifully demonstrates. A better discriminator might be global edits vs local edits, with local edits being things like retouching specific parts of the image to make d…

Sidestepping the whole discussion about "fake" and "real" images, I think what matters is what degree of correlation is there, if any, between the raw sensor data and the final photo you show your friends.

Raw data requires interpretation, no argument there.

But when AI starts making stuff up out of nowhere, it becomes a problem. Again, some degree of making up stuff is ok, but AI often crosses the line. When it diverges enough from what was captured by the sensor, it crosses firmly into "made up" territory.

Re: What an unprocessed photo looks like

#329

Post by NetMageSCW »

littlestymaar wrote: post #226
henrebotha wrote: post #208

Earlier quoted context omitted.

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”

But that qualifier in stupid because there’s no start or stopping point for ultra processed versus all foods. Is cheese an ultra-processed food? Is wine?
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