are CMYK images supported....

Interesting. I did a few tests and it appears that CKFinder has problems in IE9 when uploading CMYK pics via the dialog's Upload tab > Send it to the Server button. When I click on Browse Server then use the Upload button, it works fine. I suggest using the latter method for now until we sort it out.

August 10th, 2012
Dear Sebastian Stefanov
I have edited the original post because -my bad- I used this forum instead the support email to inform **what I believe is a bug** I used this forum originally because this was the only reference to CMYK files.
I formally apologize for my original post. It will NOT happen again. Believed bugs will be informed and support requested by the appropriate email address.
This is Michael Palacio with DXFZ653.12906 and CKFinder version 2.2 PHP, guest is MacBook Pro MacOS X 10.6.8 and Server is running CKFinder 2.2 PHP is a MacMini MacOS X 10.6.8; using Mac Safari/Firefox/Chrome to upload/download jpg in CMYK format so I can upload CMYK jpgs and the print shop can retrieve them and print them. CKFinder configuration is set to accept files up to 30MB.
In MY case i verified that if I upload a jpg file in CMYK format, CKFinder converts it to RGB and stores it that way hence the print shop downloads it in jpg RGB mode not useful for printing purposes.
(I discovered that if you zip the original CMYK and upload them, the CMYK "color space" is of course preserved; but you -of course again- can't visualize them, something needed.
You can try uploading "cymk-orig.jpg" https://www.dropbox.com/s/vutmsrlxx7fm1yz/cymk-orig.jpg (2.737.774 bytes) to CKFinder and after downloading it please verify "cymk-downloaded.jpg" https://www.dropbox.com/s/vwa65zldit9d6 ... loaded.jpg (1.317.022 bytes).
Please see attached "Get Info Files"
Perhaps I'm doing something wrong, I'm new to CKFinder but already loooooove it.
Kind regards, Michael Palacio from Buenos Aires

First of all, you must remember that CMYK images aren't supported in IE until IE9, so usually it's not a good idea to upload such images to a web page.

Second, the biggest data loss that I see on your image is that the original is 3008x3577 and the downloaded one is 1892x2250, that's a lot of pixels lost along the way!

If you adjust the configuration so that the images are not resized I think that the color space won't be changed and you'll have really the original images instead of a downsampled version.