Prophoto RGB?

[Steve Kefford]

The main problem in working with a large color space is that you have less numerical separation between two given colors than you would have with a smaller color space. When working in Prophoto, it is almost a necessity to use 16bit color. One of the flavors of Ektaspace is free, and enough of an industry standard that drum scan operators in India did not need any explanation about it.

Yes, it is essential that you use 16 bits, otherwise you won't get any advantage. I use it most of the time, but I also do digital capture. In these circumstances, I believe that it is the best overall option, especially if wanting to use a single space for all work. This of course applies to my working space, which I keep my master files in. Obviously, conversions can be made on output to suit what space is appropriate, e.g. srgb for monitor/web viewing.

Steve

[Henry Ambrose]

Even standard old non-sexy Adobe 98 is a bigger space than average monitors can display. Adobe 98 was designed for working on files destined for CMYK reproduction. Gordon's "using the numbers" is a time tested way to get what you want on press. But it'd still be nice to have one of the new monitors that will show all the colors you're working with.

Now when you veer off into even bigger working spaces (in this discussion its Prophoto) you're dealing with even more colors than can't be shown on screen and back to guessing at color even more. But if you're getting something in your print that you think makes it better then good for you. I think you're causing yourself trouble unless you have a well conceived scheme that can take advantage of the bigger space. Likely there isn't such a scheme that is valid.

What I'm saying is to think deeply about your particular situation before choosing a bigger color space. The bigger space probably won't help you.

[Bruce Watson]

The main problem in working with a large color space is that you have less numerical separation between two given colors than you would have with a smaller color space. When working in Prophoto, it is almost a necessity to use 16bit color.

Good point. I always scan and work in 16 bits; it never occurs to me to do less. After I've gone through the trouble to fluid mount film to a drum it seems a dubious value to me to settle for an 8 bit scan. But if you are working in 8 bits then certainly the larger workspaces may become problematic.

[Steve Kefford]

Even standard old non-sexy Adobe 98 is a bigger space than average monitors can display
......
What I'm saying is to think deeply about your particular situation before choosing a bigger color space. The bigger space probably won't help you.

I think it is always a good idea to work in a bigger space than your output. So. if you are only outputting to screen, then Adobe 98 is good enough. But who only outputs to screen?

If you are not going to do any editing, then that is a different situation. But even so, whilst a bigger space might not help, it won't do any harm either.

Steve

[Henry Ambrose]

I think it is always a good idea to work in a bigger space than your output. So. if you are only outputting to screen, then Adobe 98 is good enough. But who only outputs to screen?

If you are not going to do any editing, then that is a different situation. But even so, whilst a bigger space might not help, it won't do any harm either.

Steve

Its a good idea to work in a bigger space if you want to NOT SEE what you file looks like on screen and NOT SEE what your print might look like. You are defeating one of the major features of color management - that your print look like what you see on your monitor.

If you were only going to a monitor screen with the file then sRGB would be a good choice for most monitors owned by the great unwashed masses. But that is a side issue.

There can be reasons for huge color spaces but not for most people. Stay with something that fits your equipment's capability.

[Stephen Best]

If you were only going to a monitor screen with the file then sRGB would be a good choice for most monitors owned by the great unwashed masses. But that is a side issue.

There can be reasons for huge color spaces but not for most people. Stay with something that fits your equipment's capability.

This is poor advice, unless your subjects are limited to portraits etc. It's not impractical to edit Adobe RGB (or larger) files on a sRGB-ish monitor. You certainly don't want your prints limited to the lowest device gamut in the chain.

For most scans Adobe RGB (or ECI RGB, Lstar-RGB etc) is adequate. There's not a lot of real world colours outside of Adobe RGB (mainly flowers, bird plumage etc) that can also be printed. If however you want to encompass what the transparency can record, Beta or Holmes is the space to use. Prophoto RGB is just overkill.

Also, there's nothing to say that the spaces for all your images has to be the same ... in fact there are downsides to adopting such a scheme. We've moved on since Photoshop 4.

[Steve Kefford]

Its a good idea to work in a bigger space if you want to NOT SEE what you file looks like on screen and NOT SEE what your print might look like. You are defeating one of the major features of color management - that your print look like what you see on your monitor....

Then why does Photoshop provide softproofing then? For exactly when you want to see what your output looks like. Apart from the fact that most, if not all monitors, have a smaller colour gamut than any 1/2 decent desktop photo printer. So, I don't see how WYSIWYG is a major feature of colour management, when it is not possible. If all you want is WYSIWYG, then ICM Colour Management is probably not the best option, but that is going off topic.

If you were only going to a monitor screen with the file then sRGB would be a good choice for most monitors owned by the great unwashed masses. But that is a side issue.

As already said, for output, yes, but nor editing. Do you make a distinction between the two?

There can be reasons for huge color spaces but not for most people. Stay with something that fits your equipment's capability.

If you want to be able to use all the colours that a desktop printer is capable of, then using a space that has a smaller gamut then the printer makes it impossible. That is a fact, not opinion. What is also fact is that even Adobe 98 will clip most photo printers, so if you want to print as many colours as your equipment is capable of, then a large space, such as ProPhoto, is the answer. If that excludes most people, then so be it.


Steve

[Henry Ambrose]

Steve -
While Prophoto covers all the gamut of any printer, unless used properly it will cause problems. Please read Q.T.'s note about the necessity of working in 16 bit when using larger working spaces. For average users who operate an 8 bit workflow the use of extra large spaces may cause problems, particularly banding.

That WYSIWYG is not a major feature of color management is a remarkable statement.

You state: "Then why does Photoshop provide softproofing then? For exactly when you want to see what your output looks like." What good is softproofing if the monitor is physically not capable of showing some colors? Softproofing won't show you colors the monitor can't display. On one hand you state that WYSIWYG is not a major feature and then on the other you're claiming softproofing which depends on WYSIWYG. You are writing in circles. So is WYSIWYG a major feature or not? (hint: it is perhaps the major feature, indeed the holy grail from the beginning)

Stephen -
I agree its not impractical to edit Adobe 98 on an sRGB monitor. That is what we've all been doing for years. The point I was making (and not made carefully enough) is that for a photo of any subject (in this case on the web) is that for an sRGB monitor and a browser that does not color manage will only show sRGB. To get to that end point the capture, working and output can all be in sRGB as thats all the chain will support. If you send a file out without adjusting it for the space where it will be displayed you have less idea about how it will show on other's screens. This is a parallel issue to the use of large gamut working spaces for printing.

Anyway, I entered this thread not for an argument but to provide a caveat to "average 8 bit users" that simply picking an extra large color space is not necessarily a good idea. Bigger is often thought of as better but in this case its not better unless care is exercised in consideration of the overall workflow. You'll want to expand the entire workflow so that all the links function together. Extra large spaces are not the answer for everyone.

[Steve Kefford]

Steve -
While Prophoto covers all the gamut of any printer, unless used properly it will cause problems. Please read Q.T.'s note about the necessity of working in 16 bit when using larger working spaces. For average users who operate an 8 bit workflow the use of extra large spaces may cause problems, particularly banding.

I would not necessarily agree that ProPhoto covers the gamut of any printer, but thats a minor point so lets not dwell on it.

We don't disagree that 16 bits is essential. I did state this earlier. All my comments have been aimed at users (average or otherwise, whatever this means) using 16 bits. There are so many other advantages in using 16 bits, that I would expect anybody contemplating using ProPhoto would not be using 8 bits.

That WYSIWYG is not a major feature of color management is a remarkable statement.

You state: "Then why does Photoshop provide softproofing then? For exactly when you want to see what your output looks like." What good is softproofing if the monitor is physically not capable of showing some colors? Softproofing won't show you colors the monitor can't display. On one hand you state that WYSIWYG is not a major feature and then on the other you're claiming softproofing which depends on WYSIWYG. You are writing in circles.

No, I am not writing in circles. Softproofing will not show you exactly what you are going to get - it will give you an idea - and therfore does not depend on WYSIWYG.

Normally, the device with the smallest colour gamut is the monitor. If you are going to restrict your gamut to match this, then you are throwing away a lot of colour that your device (camera or film/scanner) can capture, and also a lot of colour that your printer/ink/paper can show. Thus, by restricting yourself to the lowest common denominator, you have the potential for WYSYWIG.

If instead you want to use the greater gamuts of the capture device and the printer, how then can you achieve WYSIWYG? It is not possible. If it is, then please explain.

So, is softproofing valuable in this situation? I would say absolutley, even more so, but it gives an idea, not a definitive view. This is not WYSYWIG, but it works. I have never claimed that softproofing depends on WYSYWIG. That is an assumption you have -errounously - made.

I repeat, how can the impossible (WYSYWIG) be a major feature of ICM colour management? If what you want is as close a match between the screen and your print, then ICM colour management is one option, and is not the holy grail.

I have just picked up my copy of Colo(u)r Management by one of the great gurus of the subject, the recently departed Bruce Fraser, to get a little history on the development of ICS Colour Managment. He describes under the heading "The Genesis of Colour Management" the desire to simplify the interoperability of many many different colour devices. It is not the desire to get just two devices (monitor & printer) to give WYSYWIG. If this is the aim, then much much simpler methods are available.

Next to the above, he has a sidebar entitled "The WYSIWYG Myth". In it he explains that WYSYWIG is impossible (for the reasons I outlined above, plus some others), and basically correlates the other points I have previously made.

So is WYSIWYG a major feature or not? (hint: it is perhaps the major feature, indeed the holy grail from the beginning)

So, to answer your final question, even with your ever so helpful hint, I will have to say a most definite NO. I stand by my earlier remarkable statement.

Steve

[Steve Kefford]

....To get to that end point the capture, working and output can all be in sRGB as thats all the chain will support...

Henry,

This is just not correct. The chain can support more. Just because the output will be sRGB does not mean that sRGB has to be used all the way through. Ignoring the larger space issue, Adobe RGB as a working space is a perfectly valid workflow. The chain will support it.

Steve