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What an unprocessed photo looks like

maurycyz.com

231–240 of 418 posts

Re: What an unprocessed photo looks like

#231
post #39

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…

This is also why I absolute hate, hate, hate it when people ask me whether I "edited" a photo or whether a photo is "original", as if trying to explain away nice-looking images as if they are fake. The JPEGs cameras produce are heavily processed, and they are emphatically NOT "original". Taking manual control of that process to produce an alternative JPEG with different curves, mappings, calibrations, is not a crime.

I noticed this a lot when taking pictures in the mountains.

I used to have a high resolution phone camera from a cheaper phone and then later switched to an iPhone. The latter produced much nicer pictures, my old phone just produces very flat-looking pictures.

People say that the iPhone camera automatically edits the images to look better. And in a way I notice that too. But that’s the wrong way of looking at it; the more-edited picture from the iPhone actually corrresponds more to my perception when I’m actually looking at the scene. The white of the snow and glaciers and the deep blue sky really does look amazing in real life, and when my old phone captured it into a flat and disappointing looking photo with less postprocessing than an iPhone, it genuinely failed to capture what I can see with my eyes. And the more vibrant post processed colours of an iPhone really do look more like what I think I’m looking at.

Re: What an unprocessed photo looks like

#234

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 bit about the green over-representation in camera color filters is partially correct. Human color sensitivity varies a lot from individual to individual (and not just amongst individuals with color blindness), but general statistics indicate we are most sensitive to red light. The main reason is that green does indeed overwhelmingly contribute to perceptual luminance (over 70% in sRGB once gamma corrected: https:…

> 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?

Re: What an unprocessed photo looks like

#235
post #39

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…

This is also why I absolute hate, hate, hate it when people ask me whether I "edited" a photo or whether a photo is "original", as if trying to explain away nice-looking images as if they are fake. The JPEGs cameras produce are heavily processed, and they are emphatically NOT "original". Taking manual control of that process to produce an alternative JPEG with different curves, mappings, calibrations, is not a crime.

I don't think it's the same, for me personally I don't like heavily processed images. But not in the sense that they need processing to look decent or to convey the perception of what it was like in real life, more in the sense that the edits change the reality in a significant way so it affects the mood and the experience. For example, you take a photo on a drab cloudy day, but then edit the white balance to make it seem like golden hour, or brighten a part to make it seems like a ray of light was hitting that spot. Adjusting the exposure, touching up slightly, that's all fine, depending on what you are trying to achieve of course. But what I see on instagram or shorts these days is people comparing their raws and edited photos, and without the edits the composition and subject would be just mediocre and uninteresting.

Re: What an unprocessed photo looks like

#236

This is actually really useful. A lot of people demand an "unprocessed" photo but don't understand what they're actually asking for.

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. The camera isn’t even set to produce a JPEG + RAW combo, so there is literally no reference.

Re: What an unprocessed photo looks like

#237

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 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. (⩺_⩹)

If the Bayer pattern makes you angry, I imagine it would really piss you off to realize that the whole concept encoding an experienced color by a finite number of component colors is fundamentally species-specific and tied to the details of our specific color sensors.

To truly record an appearance without reference to the sensory system of our species, you would need to encode the full electromagnetic spectrum from each point. Even then, you would still need to decide on a cutoff for the spectrum.

...and hope that nobody ever told you about coherence phenomena.

Re: What an unprocessed photo looks like

#238
post #113

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…

Just wait a few years, all of this is still getting better.

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.

Re: What an unprocessed photo looks like

#239
post #159

Earlier quoted context omitted.

Green is in the center of the visible spectrum of light (notice the G in the middle of ROYGBIV), so evolution should theoretically optimize for green light absorption. An interesting article on why plants typically reflect that wavelength and absorb the others: https://en.wikipedia.org/wiki/Purple_Earth_hypothesis

Green is the highest energy light emitted by our sun, from any part of the entire light spectrum, which is why green appears in the middle of the visible spectrum. The visible spectrum basically exists because we "grew up" with a sun that blasts that frequency range more than any other part of the light spectrum.

That comment does not make sense. Do you mean the sun emits it's peak intensity at green (I don't believe that is true either, but at least it would make a physically sensical statement). To clarify why the statement does not make sense, the energy of light is directly proportional to its frequency so saying that green is the highest energy light the sun emits is saying the sun does not emit any light at frequency higher than green, i.e. no blue light no UV... That's obviously not true.

Re: What an unprocessed photo looks like

#240

I studied remote sensing in undergrad and it really helped me grok sensors and signal processing. My favourite mental model revelation to come from it was that what I see isn’t the “ground truth.” It’s a view of a subset of the data. My eyes, my cat’s eyes, my cameras all collect and render different subsets of the data, providing different views of the subject matter. It gets even wilder when perceiving space and ti…

Yup. I had the same revelation when I learned that many of the colors we perceive don't really "exist". The closest thing to hue in nature is wavelength, but there is no wavelength for purple, for example. The color purple is our visual system's interpretation of data (ratio of trichromatic cone cell activation). It doesn't exist by itself.

It's the same reason that allows RGB screens to work. No screen has ever produced "real" yellow (for which there is a wavelength), but they still stimulate our trichromatic vision very similar to how actual yellow light would.

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