Mike Chaney's Tech Corner

Technical Discussions => Computer Software => Topic started by: Terry-M on May 31, 2009, 08:09:34 PM



Title: Colour Gamut Visualisation
Post by: Terry-M on May 31, 2009, 08:09:34 PM
This section is still empty, so I’ll rectify that.
I thought I’d posted this as an OT topic on the Yahoo group, but I can’t find it now so here is another version.
Many will know of the Windows XP “Color Control Power Toy” that is able to visualise colour gamuts in 3D. However only two icc profiles can be compared and it is not available for Vista.
There are some sophisticated programs for this purpose with various other tools but a simple free one is available from
http://www.tglc.com/english/PerfX/3D_Gamut_Viewer.html.
It allows up to 4 profiles to be compared and will work with Vista. There’s no installer provided but it’s easy to create your own program folder and shortcuts.

You might ask why bother with this? I agree it’s a bit of a toy but can be useful in helping to understand some aspects of colour management and the meaning of gamut.
Here is an example of a comparison I have done:

(http://www.pbase.com/tjm04/image/113131126/original.jpg)



The individual screen captures for the above compilation are here: http://www.pbase.com/tjm04/gamut

Terry.


Title: Re: Colour Gamut Visualisation
Post by: Fred A on June 01, 2009, 11:49:08 AM
Terry,
Thank you for posting this learning tool.
Might I ask, If the gamut of my printer is smaller than my camera's, why should I be overly concerned about huge color space selection when "developing" my image?
Fred


Title: Re: Colour Gamut Visualisation
Post by: Terry-M on June 01, 2009, 01:42:02 PM
Hi Fred,
I think you can see that on the top view and the bottom view with the projection lines, the smallest gamut is the printer and the largest is the camera raw. Jpegs from camera are also larger than the printer in most areas too. That's certainly the case for a Canon 350D and Epson R800 and I aways understood that the R800/1800 had an excellent gamut.
From what I have seen with my equipment, Adobe RGB is plenty big enough. However I usually print from raw and therefore utilise the camera gamut by having a camera profile activated in Qimage SE.
Terry.


Title: Re: Colour Gamut Visualisation
Post by: Fred A on June 01, 2009, 04:02:35 PM
Thanks for the quick reply again. I have a Canon 20D utilizing the camera profile that I got from Mike Chaney's camera profiles, in Raw mode into Qimage and into my R 1800.
Is the R1800 Epson gamut the same as the R800?
I believe the inks are the same.
I generally use Epson Prem glossy and also a lot of Ilford Smooth gloss.

How about paper like Ilford Pearl or Epson Prem Luster?
Any change in gamut when the paper is changed?

Fred


Title: Re: Colour Gamut Visualisation
Post by: Terry-M on June 01, 2009, 04:50:20 PM
Fred,
You are making me do all the work ;-)
There appear to be some differences between the gamuts R800 & 1800. I compared Smooth Gloss  & Pearl Ilford profiles and the R800 had a bit more in the blue-green area (-a axis).
There is no significant difference between Pearl & Gloss based on my custom profiles.

I do note that Ilford Fine Art paper has a significantly smaller gamut than Pearl or Gloss so that surprises me especially when many pro's advertise their prints as being printed on fine art type paper. Are we missing something? When I tried it I was disappointed, shadow areas were not good. I do use archival matt, Epson & Ilford versions, and the look is similar to the fine art paper I tried.

Have you d/l the little program yet, you can then try all this for yourself.
Terry.


Title: Re: Colour Gamut Visualisation
Post by: Terry-M on June 01, 2009, 06:15:12 PM
One thing I missed out in my initial post was that the camera profile for use in Qimage SE for RAW processing was one I made with Profile Prism.
However, they are available from DDI as Fred has indicated.
Terry.


Title: Re: Colour Gamut Visualisation
Post by: Fred A on June 01, 2009, 09:21:23 PM
Yes, I have D/L the little program.... will play with it tomorrow.
Fred


Title: Re: Colour Gamut Visualisation
Post by: daniellouwrens on June 04, 2009, 09:07:48 PM
Hi

has anyone D/L this in the last couple of hours, I cannot get through, I get a "not found" error.

When I run tracert I get "timed out" on the last 10 or so attempts.

If no one else is having any problems it must be my ISP.

Thanks

Daniel


Title: Re: Colour Gamut Visualisation
Post by: Terry-M on June 04, 2009, 09:16:10 PM
No problem here in getting to the web site.
Terry.


Title: Re: Colour Gamut Visualisation
Post by: daniellouwrens on June 05, 2009, 07:40:55 PM
Thanks Terry,

I just got in, thanks for the heads up on this little gem.

regards

Daniel


Title: Re: Colour Gamut Visualisation
Post by: jwinberg1 on July 01, 2009, 01:37:40 PM
Wow, Terry:

I just saw and downloaded this gem of a software, and am really grateful!

THANKS........ Jack Winberg


Title: Re: Colour Gamut Visualisation
Post by: rayw on November 12, 2009, 01:36:01 AM
Hi Terry,

I have spent some time getting headaches, trying to interpret these 3d shapes produced by the M$ color toy. I think if i were able to mould them in some sort of coloured jelly, (is that jello in usa? ) I would still have problems. However, a more easily -at least for me- visual representation can be found here http://www.fho-emden.de/~hoffmann/hungams17042004.pdf

There is also a 9 sliced version by someone else here - http://www.curvemeister.com/tutorials/gamutviewer/index.htm  which is easier to visualise, but less 'precise', but you can load many copies into one photoshop/whatever window.

Best wishes,

Ray


Title: Re: Colour Gamut Visualisation
Post by: Terry-M on November 12, 2009, 11:18:57 AM
Ray,
Quote
I have spent some time getting headaches, trying to interpret these 3d shapes produced by the M$ color toy. I think if i were able to mould them in some sort of coloured jelly, (is that jello in usa? ) I would still have problems.
Thanks for the extra information, I'll have a look at those later.
My own view on all of these visualisations is they're "toys" for most photographers. They give a better understanding of the difference between camera, monitor, any intermediate space used and printer.
It's not worth getting a headache over it.  ;)
Terry