On 10/20/07, Mark <[EMAIL PROTECTED]> wrote: > But then, I have created profiles (LUT and matrix) for some > industrial cameras - RAW image directly from sensor, debayered, > linear = gamma 1.0 - and I can only say that I see a very huge > difference in image quality between LUT and matrix profiles. Almost > all packages for profiling digital cameras create LUT profiles > nowadays. Why?
I guess because a LUT profile will always work, no matter how strange the camera (fuji's two sensors per site, nikon's CMYG filters, sony's RGBC), whereas a matrix profile requires camera filters which are close to a linear recombination of XYZ and not too much unknown processing before the profile is applied. I don't know why you saw a quality improvement with a LUT profile. I've always had better results with a matrix on the cameras I've worked on. Image quality is hard to quantify. > As for scanners - which really are digital cameras with one fixed > illuminant - almost all profiling packages also create LUT based > profiles. Why? Most scanners are designed to scan photographic or print material where your profile has to fix up those (very non-linear) processes as well as the CCD + filter. Most flatbeds have narrowband filters, rather than the broad filters in a camera, because they are designed to measure dye density rather than colour. John ------------------------------------------------------------------------- This SF.net email is sponsored by: Splunk Inc. Still grepping through log files to find problems? Stop. Now Search log events and configuration files using AJAX and a browser. Download your FREE copy of Splunk now >> http://get.splunk.com/ _______________________________________________ Lcms-user mailing list Lcms-user@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/lcms-user
