Reported V4.25 ... V4.00 Colorspace CMYK problem

[mikesum32]

It seems CMYK colors are way over-saturated, at least as how they look in photoshop 7(created with) and mspaint(a little under-saturated).

Probably same problem as http://irfanview-online.com/vb/showthread.php?t=145

[Sjef]

IrfanView is a RGB-viewer/convertor. So first you have to convert your CMYK image to RGB. See also:

http://irfanview-online.com/vb/showthread.php?t=145

[mikesum32]

Well it handles CMYK and apparently LAB color, just not very well. It needs to support CMYK correctly or not at all.

[Sjef]

Did you also use the free programs FastStone Viewer, or XnView? Or payd programs like ACDSee, CompuPic Pro of even PaintShop Pro? Try them and you'll see that IV at any rate appears to show CMYK and LAB colors allright. Also the Windows standard Viewer can show CMYK (not LAB-tif's).

[Christopher]

Rescuscitating an old thread here, but with good reason... (it's highly ranked in Google so seems the logical place to discuss this).


Sad to see that even in the latest builds of IrfanView, CMYK support isn't 100% correct - oversaturated, incorrect colours. As a graphic designer I would be in review nirvana if IV only supported CMYK fully! I always have to use Photoshop to preview my CMYK renders, which is a crying shame as I have IV set as the default viewer for all images on my machines.

I'm sure many people who work with CMYK imagery are just as keen to see IV correctly support the CMYK (and Lab) colourspace as I am... Is it ever going to happen?

[Sjef]

There are lots and lots of CMYK formats (coated FOGRA, Euroscale, US Sheetfat Coated, etc.). Which format do you want IV to support properly? IV can show the picture and tries everything to do it right, providing you have set the 'Enable color management (plugin)' in Properties/Settings/Viewing. But then you can be surprised over other strange color profiles, like there are in Tif or JPG (with e-sRGB). Same story about the many different Raw formats. All viewers show different colors (IV even shows the artefacts) and the only 'trough' color is to be viewed after converting with a special program or a plugin.

I agree it would be nice to have a IV-plugin which shows a lot of CMYK-profiles, like the RGB-plugin does for RGB profiles. But is it a guarantee for the right colours on paper?

[Christopher]

There are lots and lots of CMYK formats (coated FOGRA, Euroscale, US Sheetfat Coated, etc.). Which format do you want IV to support properly? IV can show the picture and tries everything to do it right, providing you have set the 'Enable color management (plugin)' in Properties/Settings/Viewing. But then you can be surprised over other strange color profiles, like there are in Tif or JPG (with e-sRGB). Same story about the many different Raw formats. All viewers show different colors (IV even shows the artefacts) and the only 'trough' color is to be viewed after converting with a special program or a plugin.

I agree it would be nice to have a IV-plugin which shows a lot of CMYK-profiles, like the RGB-plugin does for RGB profiles. But is it a guarantee for the right colours on paper?

I guess my benchmark for accurate CMYK reproduction would be "values as they appear in any professional image editor" - I usually work in a standard colour space, but even just a plugin would be nice (or included facility) which would let you preset the max ink levels and choose which standard (US, EU, Japan) you work with.

It just seems a real shame that the default gamut reproduction for CMYK images seems so off Is there a particularly complex reason behind it? Even Windows can handle near enough all CMYK images and reproduce them far more accurately than IV, which is the one thing which stops me recommending it without question to every other designer I know

[Sjef]

I guess my benchmark for accurate CMYK reproduction would be "values as they appear in any professional image editor"

I converted an RGB-file (chimney.jpg, see attachment) to CMYK and gave it the standard color profile 'Photoshop 5 CMYK'.

Then I tried different programs on the file to compare the colors.

ACDSee 2 Pro doesn't show the right colors, even if Photoshop5DefaultCMYK.icc is chosen (too much Magenta). That's a 'professional' viewer one may assume.
Another 'pro' is Corel Xara. Doesn't support such a CMYK file eighter, like Pencil doesn't.
RealDraw does support CMYK, but the file is also too Magenta, same as PhotoLine, PhotoFiltre, CompuPic Pro, FastStone and XnView.

Only Pain.net, PhotoScape and Windows (paint) supports this CMYK file.

And of course IrfanView (with plugin on).