Why does Lightroom (and Photoshop) use AdobeRGB and/or ProPhoto RGB as default color spaces, when most monitors are standard gamut (sRGB) and cannot display the benefits of those wider gamuts?

Question

I've asked this in a couple other places online as I try to wrap my head around color management, but the answer continues to elude me. That, or I've had it explained and I just didn't comprehend. So I continue. My confusion is this: everywhere it seems, experts and gurus and teachers and generally good, kind people of knowledge claim the benefits (in most instances, though not all) of working in AdobeRGB and ProPhoto RGB. And yet nobody seems to mention that the majority of people - including presumably many of those championing the wider gamut color spaces - are working on standard gamut displays. And to my mind, this is a huge oversight. What it means is, at best, those working this way are seeing nothing different than photos edited/output in sRGB, because [fortunately] the photos they took didn't include colors that exceeded sRGB's real estate. But at worst, they're editing blind, and probably messing up their work. That landscape they shot with all those lush greens that sRGB can't handle? Well, if they're working in AdobeRGB on a standard gamut display, they can't see those greens either. So, as I understand it, the color managed software is going to algorithmically reign in that wild green and bring it down to sRGB's turf (and this I believe is where relative and perceptual rendering intents come into play), and give them the best approximation, within the display's gamut capabilities. But now this person is editing thinking they're in AdobeRGB, thinking that green is AdobeRGB's green, but it's not. So any changes they make to this image, they're making to an image that's displaying to their eyes as sRGB, even if the color space is, technically, AdobeRGB. So they save, output this image as an AdobeRGB file, unaware that [they] altered it seeing inaccurate color. The person who opens this file on a wide gamut monitor, in the appropriate (wide gamut) color space, is now going to see this image "accurately" for the first time. Only it was edited by someone who hadn't seen it accurately. So who know what it looks like. And if the person who edited it is there, they'd be like, "wait, that's not what I sent you!"
Am I wrong? I feel like I'm in the Twilight Zone. I shoot everything RAW, and I someday would love to see these photos opened up in a nice, big color space. And since they're RAW, I will, and probably not too far in the future. But right now I export everything to sRGB, because - internet standards aside - I don't know anybody who I'd share my photos with, who has a wide gamut monitor. I mean, as far as I know, most standard gamut monitors can't even display 100% sRGB! I just bought a really nice QHD display marketed toward design and photography professionals, and I don't think it's 100. I thought of getting the wide gamut version, but was advised to stay away because so much of my day-to-day usage would be with things that didn't utilize those gamuts, and generally speaking, my colors would be off. So I went with the standard gamut, like 99% of everybody else.
So what should I do? As it is, I have my Photoshop color space set to sRGB. I just read that Lightroom as its default uses ProPhoto in the Develop module, and AdobeRGB in the Library (for previews and such).
Thanks for any help!
Michael

Answer 1

Okay. Going bigger is better, do so when you can (in 16-bit). Darn, those TIFs are big though. So, ideally, one really doesn't want to take the picture to Photoshop until one has to, right? Because as long as it's in LR, it's going to be a comparatively small file (a dozen or two MBs vs say 150 as a TIF). And doesn't LR's develop module use the same 'engine' or something, as ACR plug-in? So if your adjustments are basic, able to be done in either LR Develop, or PS ACR, all things being equal, choose to stay in LR?
ssprengel Apr 28, 2015 9:40 PM
PS RGB Workspace:  ProPhotoRGB and I convert any 8-bit documents to 16-bit before doing any adjustments.
Why does one convert 8-bit pics to 16-bit? Not sure if this is an apt comparison, but it seems to me that that's kind of like upscaling, in video. Which I've always taken to mean adding redundant information to a file so that it 'fits' the larger canvas, but to no material improvement. In the case of video, I think I'd rather watch a 1080p movie on an HD (1080) screen (here I go again with my pixel-to-pixel prejudice), than watch a 1080p movie on a 4K TV, upscaled. But I'm ready to be wrong here, too. Maybe there would be no discernible difference? Maybe even though the source material were 1080p, I could still sit closer to the 4K TV, because of the smaller and more densely packed array of pixels. Or maybe I only get that benefit when it's a 4K picture on a 4K screen? Anyway, this is probably a different can of worms. I'm assuming that in the case of photo editing, converting from 8 to 16-bit allows one more room to work before bad things start to happen?
I'm recent to Lightroom and still in the process of organizing from Aperture. Being forced to "this is your life" through all the years (I don't recommend!), I realize probably all of my pictures older than 7 years ago are jpeg, and probably low-fi at that. I'm wondering how I should handle them, if and when I do. I'm noting your settings, ssprengel.
ssprengel Apr 28, 2015 9:40 PM
I save my PS intermediate or final master copy of my work as a 16-bit TIF still in the ProPhotoRGB, and only when I'm ready to share the image do I convert to sRGB then 8-bits, in that order, then do File / Save As: Format=JPG.
Part of the same question, I guess - why convert back to 8-bits? Is it for the recipient?  Do some machines not read 16-bit? Something else?
For those of you working in these larger color spaces and not working with a wide gamut display, I'd love to know if there are any reasons you choose not to. Because I guess my biggest concern in all of this has been tied to what we're potentially losing by not seeing the breadth of the color space we work in represented while making value adjustments to our images. Based on what several have said here, it seems that the instances when our displays are unable to represent something as intended are infrequent, and when they do arise, they're usually not extreme.
Simon G E Garrett Apr 29, 2015 4:57 AM
With 8 bits, there are 256 possible values.  If you use those 8 bits to cover a wider range of colours, then the difference between two adjacent values - between 100 and 101, say - is a larger difference in colour.  With ProPhoto RGB in 8-bits there is a chance that this is visible, so a smooth colour wedge might look like a staircase.  Hence ProPhoto RGB files might need to be kept as 16-bit TIFs, which of course are much, much bigger than 8-bit jpegs.
Over the course of my 'studies' I came across a side-by-side comparison of either two color spaces and how they handled value gradations, or 8-bit vs 16-bit in the same color space. One was a very smooth gradient, and the other was more like a series of columns, or as you say, a staircase. Maybe it was comparing sRGB with AdobeRGB, both as 8-bit. And how they handled the same "section" of value change. They're both working with 256 choices, right? So there might be some instances where, in 8-bit, the (numerically) same segment of values is smoother in sRGB than in AdobeRGB, no? Because of the example Simon illustrated above?
Oh, also -- in my Lumix LX100 the options for color space are sRGB or AdobeRGB. Am I correct to say that when I'm shooting RAW, these are irrelevant or ignored? I know there are instances (certain camera effects) where the camera forces the shot as a jpeg, and usually in that instance I believe it will be forced sRGB.
Thanks again. I think it's time to change some settings..