Printing - sRGB and Adobe questions

[Macmahon]

For the record: even though a browser may be color-managed, that does not mean that it is displaying colors accurately. To demonstrate that, try a bunch of browsers viewing the same photos and determine which ones don't display your photos on the Internet the same as when using your post-processing software.

I use Firefox because it displayed an image properly when Explorer and Chrome did not. I realize that that's neither scientific nor exhaustive, but based on my anecdotal experience I'm happy with Firefox so far.

Me too. Safari and Firefox are properly colour managed out of the box. Chrome isn't and neither was any version of Internet Explorer that I ever used. There's a great site where you can check your browser here.

Cheers

Tim

[Colin Southern]

Most of the debate is around 5000K vs 6500K.

The official standard is supposed to be D50 (so 5000 Kelvin), but personally, I stick with 6500K, as I find it far more comfortable on the eye. I suspect a lot of others do the same.

[Colin Southern]

Hmmm. Actually the default working space for Lightroom, and AFIAK, ACR (Adobe Camera Raw - the raw convertor part of Photoshop) is a modified version of ProPhoto (called Melissa RGB): it has the same colour primaries as ProPhoto, but a linear tonal response curve, i.e. a gamma of 1 rather than
...

Hi Tim, not quite ...

- LR and ACR use ProPhoto with linear gamma

- Melissa RGB is ProPhoto size, but with sRGB gamma (modified 2.2)

- Only place LR uses Melissa RGB is for colour read outs and the histogram.

Working in linear gamma makes sense as it avoids compromising data in RAW captures - it's just not good for humans to work with.

[Brownbear]

Thank you Richard, Colin, Mike, John and Tim for advising and sharing a wealth of information. I'm still in Mexico (not on vacation), but when I return I will revisit this thread and review all the information, which I'm sure will be very helpful to me.

Thank you to all.

[Macmahon]

Hi Tim, not quite ...

- LR and ACR use ProPhoto with linear gamma

- Melissa RGB is ProPhoto size, but with sRGB gamma (modified 2.2)

- Only place LR uses Melissa RGB is for colour read outs and the histogram.

Working in linear gamma makes sense as it avoids compromising data in RAW captures - it's just not good for humans to work with.

True. I shouldn't have referred to Melissa - she would have been upset. The main point was/is that the working space of both LR and ACR is one that has very wide primaries (includes every conceivable colour) and has a linear tonal response 'curve', i.e. gamma = 1.

Tim

[Richard Lundberg]

Of course it they have a linear tonal response, but you don't open an image that way. Unless you're a lemur or a bat.

[Colin Southern]

True. I shouldn't have referred to Melissa - she would have been upset. The main point was/is that the working space of both LR and ACR is one that has very wide primaries (includes every conceivable colour) and has a linear tonal response 'curve', i.e. gamma = 1.

Tim

Yep. I use ProPhoto too, but I do like to say to people that "with great power comes great responsibility"; in the case of a wide space like ProPhoto folks can end up manipulating colours that they can't see - so they change them to something that "looks right" (but is actually wrong), and they then wonder why they print as something completely different.

For some folks it's just easier for them to stick with sRGB right through the workflow, and then there's no nasty surprises. Yes, it is a smaller space, but that doesn't necessarily mean it's not more than adequate for a great many images. Horses for courses -- some folks seem to almost have a religious fervor that "no color can ever be lost -- so use ProPhoto" whereas in reality, most people wouldn't notice the difference in an image with a ProPhoto gamut -v- an sRGB one.

@ Christina - an old saying some to mind ...

We have not succeeded in answering all our problems. The answers we have found only serve to raise a whole set of new questions. In some ways we feel we are as confused as ever, but we believe we are confused on a higher level and about more important things.

[Mike Buckley]

in the case of a wide space like ProPhoto folks can end up manipulating colours that they can't see - so they change them to something that "looks right" (but is actually wrong), and they then wonder why they print as something completely different.

For some folks it's just easier for them to stick with sRGB right through the workflow, and then there's no nasty surprises. Yes, it is a smaller space, but that doesn't necessarily mean it's not more than adequate for a great many images.

Thank you, thank you, thank you to Colin!

I mentioned on another forum a few years ago explaining that that is exactly why I use sRGB throughout my entire workflow. Doing so was so sacrilegious to the participants of that forum that everyone (narrow mindedly in my opinion) piled on explaining all the blah blah about the importance of working with the widest possible color space available at each part of the workflow. I'm thick-skinned and didn't take it personally, but I've never mentioned it publicly since then because I would have expected the same unhelpful response that, in my opinion, is misleading especially to novices.

I've always wondered about the merit of working with a wide color space and not using a wide-gamut monitor, which of course is relatively expensive. Yet very few people who post-process using a wide color space use a wide-gamut monitor. I don't mean that as a criticism; I literally have always wondered because I've never used a wide-gamut monitor.

[ajohnw]

I have watched a video of some one working on procolour adjusting saturation. The way he did it was to in this case increase saturation of a colour until it didn't alter the image on the monitor and then back off by some amount that I assume comes with lots and lots of practice. I assume at some point he prints and if not satisfactory does it again. it's possible to see if some one does a lot of this sort of thing they probably will be able to hit what they are after by visualising the effect in the print

As to looking at gamuts one the web it's a bit difficult as they are shown in sRGB so can't show the colours that are being lost. or I suspect the sRGB gamut either.

[Colin Southern]

Thank you, thank you, thank you to Colin!

I mentioned on another forum a few years ago explaining that that is exactly why I use sRGB throughout my entire workflow. Doing so was so sacrilegious to the participants of that forum that everyone (narrow mindedly in my opinion) piled on explaining all the blah blah about the importance of working with the widest possible color space available at each part of the workflow. I'm thick-skinned and didn't take it personally, but I've never mentioned it publicly since then because I would have expected the same unhelpful response that, in my opinion, is misleading especially to novices.

I've always wondered about the merit of working with a wide color space and not using a wide-gamut monitor, which of course is relatively expensive. Yet very few people who post-process using a wide color space use a wide-gamut monitor. I don't mean that as a criticism; I literally have always wondered because I've never used a wide-gamut monitor.

You're welcome Mike!

I often find that there's a lot of "passion" around some of these mantras (and there are many). I put most of it down to there being a lot of Lemmings/Sheeple - they read something somewhere (often from a "review") - note that it appears to make sense - and then adopt it as mantra & (in an attempt to appear knowledgeable) repeat it to all who will listen. The only problem is that they don't have the practical experience to give it a proper weighting in the real world (Kinda like "don't throw stones into the sea -- it contributes to rising ocean levels"; in theory it's true, but in practice of course it's just ridiculous).

If someone is shooting a very colourful garden scene then yes - it may make a difference - (albeit one that many probably won't notice anyway). If someone is shooting a model in a studio, or a typical landscape, it's not going to matter a damn.

[Colin Southern]

I have watched a video of some one working on procolour adjusting saturation. The way he did it was to in this case increase saturation of a colour until it didn't alter the image on the monitor and then back off by some amount that I assume comes with lots and lots of practice. I assume at some point he prints and if not satisfactory does it again. it's possible to see if some one does a lot of this sort of thing they probably will be able to hit what they are after by visualising the effect in the print

Good luck to them; subtle saturation changes are bloody difficult to see. It's far easier to just soft-proof with a gamut alert turned on; as soon as areas start to turn gray (Photoshop) you know clipping is occurring in the (simulated) target device.

[ajohnw]

The thing that gets me Colin is that unless some one prints me the triangles on the full human vision spectrum I can't have any idea what colours I am missing even between one and another. And ideally I need it in 3d as well. Colours can go out of gamut as they move up vertically from the usual flat diagram.

I would guess that the differences are fairly subtle. He was using PS and if subtle I could see some one learning to work that way. To demonstrate he used something posher than this

http://www.gamutvision.com/

I don't know how important this is really for most things as cameras can't accurately mimic the real world anyway. The problems come about because of lighting with different spectrums when those are mixed. That can include the reflected light from 2 different fabrics that visually look the same - good job people usually wear suits and suitable dresses at weddings but it can be impossible to get say a white dress and some colour of suit correct at the same time without local intervention.

John
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[Macmahon]

...
If someone is shooting a very colourful garden scene then yes - it may make a difference - (albeit one that many probably won't notice anyway). If someone is shooting a model in a studio, or a typical landscape, it's not going to matter a damn.

Except where the bride's mother was wearing a deep cyan jacket that was rendered blue by sRGB. That cost. Never again.

Cheers

Tim

[Andrew76]

Except where the bride's mother was wearing a deep cyan jacket that was rendered blue by sRGB. That cost. Never again.

Cheers

Tim

OK, I thought I had it there for a second, then this post lost me. Sorry for the newbie questions. But if computer monitors can only display sRGB, and printers only print sRGB, then wasn't the deep Cyan lost before it even started?

***EDIT - never mind, I figured it out. I mis-read that printers can ONLY print sRGB.

[Macmahon]

OK, I thought I had it there for a second, then this post lost me. Sorry for the newbie questions. But if computer monitors can only display sRGB, and printers only print sRGB, then wasn't the deep Cyan lost before it even started?

Nope. The printer's gamut is way wider than sRGB in the cyans (and some other colours too). That's the problem. You can see a representation of the measured gamut of my printer compared to sRGB and 'human vision' here.

The cyan is out-of-gamut (OOG) for a (roughly sRGB) monitor so renders the colour incorrectly whereas the printer can print it more correctly. I was a victim here of trying to follow the 'only deal with what you can see' syndrome. And lost the (gamut) plot, and the client.

FWIW I now own a wide-gamut monitor and can see more of the cyans. Nevertheless in any given image there are bound to be some more highly saturated colure that are OOG for the monitor, (as well as for the printer.)

The interesting thing is that it is easy to demonstrate where you can lose colour by restricting to sRGB - as my experience with the cyan jacket (among others involving landscape sunsets and the like) shows.

I think it's less easy to demonstrate that, by editing on an 'ordinary' gamut monitor, OOG colours have 'caused problems' in print. In theory, something odd could be happening to OOG colours while you're editing. In practice, any alterations are likely to be relative to the adjustments you're making 'in-gamut' and therefore not result in anything deleterious at all. At any rate, I've never experienced anything odd, in practice. YMMV.

In terms of the sRGB-only advice, I can see why people do it, and particularly if no one is going to miss the missing colours. It's satisfying only because we choose to work within the limitation that the monitor is the weakest link (it is ... both in terms of resolution and colour gamut) in the image chain. I think of it as the 'lowest-common-denominator' approach. Safe, but...

Nevertheless, wide-gamut monitors are becoming more available and less expensive. I would guess that in time they will be commonplace and used by the majority of photographers. At that point the perceived common wisdom will change I suppose.

Cheers

Tim

Edit: Whoops. Sorry Andrew. Your edit came in while I was typing. Don't want to be "Teaching Grandma to suck eggs" as the saying goes.

[Andrew76]

Edit: Whoops. Sorry Andrew. Your edit came in while I was typing. Don't want to be "Teaching Grandma to suck eggs" as the saying goes.

No problem at all, Tim! I appreciate the explanation - it reinforces what I understand, which is scary!

[Mike Buckley]

Nice explanation, Tim.

I remember awhile back when you posted your situation with the dress of the bride's mother. That makes sense to me and emphasizes Colin's (and my) feeling that many, many photographs are just fine using an sRGB workflow. That of course implies that there are exceptions, especially depending on expectations of those reviewing the images.

In terms of the sRGB-only advice, I can see why people do it, and particularly if no one is going to miss the missing colours. It's satisfying only because we choose to work within the limitation that the monitor is the weakest link (it is ... both in terms of resolution and colour gamut) in the image chain. I think of it as the 'lowest-common-denominator' approach. Safe, but...

My choice to use an sRGB-only workflow has to do with one very simple concept that doesn't have anything to do with safety: I want all of my images to look as reasonably the same as I can whether they're displayed on the Internet, displayed using only my computer, or displayed in print. I realize that the medium of print has characteristics that are necessarily different from the other two, but I can't do anything about that. Even so, at least I'm displaying the same color space in all three situations.

Great discussion!

[Colin Southern]

Hi Andrew,

Basically ...

Monitors start with a black screen and add red, green, and blue - so no problem reproducing these colours.

Printers start with a white "screen" and add cyan, magenta, and yellow ink - so have no problem with those colours.

So in a way, the strengths of one are the weaknesses of others (cyan nulls red, green nulls magenta etc).

[ajohnw]

The only annoying aspect about wide gamut monitors is that some dither 10 bits from 8 and don't mention it. Tftcentral sometimes dismantles them to find out.via the manufacturers id on the panel. If there is one thing I hated on early monitors it was dithering to obtain extra colours.

I've no idea if this form of dithering looks the same as the old type but if it did and I noticed it I would probably throw it in the bin or stick a fist through it. Hence stick with sRGB. And also because that is what I want to work in. Panel back lighting was another consideration but that one may have sorted itself out by now.

Would you believe OpenSuse (the linux I use) dithered a shade of blue black for the desktop background. When I bought this monitor and plugged it in I came near to sending it back and then realised what caused it. It looked absolutely awful.

John
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[Colin Southern]

Except where the bride's mother was wearing a deep cyan jacket that was rendered blue by sRGB. That cost. Never again.

Cheers

Tim

She deserved it for wearing such a colour!

That a good reason to be shooting RAW though -- at least one can go back and re-process if needed. sRGB can handle cyans, but not at all levels.