CompuServe Thread

#Color matching problem

6 messages in this thread
#88048From: Ken Loss-CutlerMar 2, 1994 4:13 PM
OK, we just had a "not so nice experience" with some animation that was intended to marry with sequences created in Photostyler. It seems to us that the dial-in color values in that software and 3DS are not the same. (and I don't mean "just a bit off" either). Does anyone have any experience in this? Ken
#88148From: Yost GroupMar 2, 1994 9:02 PM
(Gawd, I hesitate to get into this, but…) My experience with the new Photostyler is that its Kodak color system assumes that gamma correction is stored with all images that it loads. Gamma correction _is_ stored with all Kodak PhotoCD images, and with some Targa and BMP files, but other apps, such as Altamira Composer, assume no gamma correction. I also found no way in Photostyler to turn off this assumption, so I ended up setting its monitor calibration to some extreme value, like 3.6 just to get my images to look normal in Photostyler. I should add that I haven't spent a great deal of time on this because I don't really use Photostyler that much (and definitely lost hope on it with the Kodak color system). On the other hand I haven't heard any complaints from others about the Kodak color system,so maybe there's some way to adjust it that I couldn't find. – Jack
#88395From: Jim LammersMar 3, 1994 3:31 PM
>> My experience with the new Photostyler is >> that its Kodak color system assumes that >> gamma correction is stored with all images that it loads. I've had the same sort of problems. The only thing I can think of is to re-install Photoshop with the Kodak thing turned off. It offers that option during the install process. But once it's in, it seems to be on for good. And then all the pasted in images, in fact all images that I've used, have this totally screwed up 'cranked-gamma' look. Not good. Jim
#88695From: Yost GroupMar 4, 1994 11:15 AM
Good to know someone else has noticed this problem. Amazing that Photostyler doesn't have a way of turning off assumed gamma-correction. I'm not sure that re-installing will help. It's possible that Photostyler assumes in-file gamma correction as a default.
#88457From: krazy imagesMar 3, 1994 7:39 PM
Jack, Just disable gamma correction for your monitor and load the images with the default 1.8 gamma PT. Styler behaves as any other image editing program that way. The KPCMS doesn't assume anything about your image. It doesn't work with the file format but with the origin of the image. In the case of opening a PhotoCD image, you can specify the source of the PCD image (i.e. used film) and the KPCMS will look in its database to ensure a _perfect_ matching with the original (assuming that you have a well configured monitor). This is the objective of the KPCMS: ensure color matching and accuracy in the whole printing production process, from the originals to camera ready output. But regarding the monitor gamma correction. Actually it will always be better to have an external correcting device to calibrate your monitor but if you don't have the money nor the knowledge/patience to do that for yourself (althought this process have changed dramatically throughtout the years) you can try to use the monitor calibration. The KPCMS allways assume that you have a 1.8 gamma monitor. If you have a calibration device, you can put establish your gamma to 1.8. If you don't have one, you can specify the real gamma in the Styler Gamma box and it will tweak with your monitor to make it 1.8. If you didn't use gamma correction in Styler neither in 3ds, your images will look exactly the same. You should be aware that the Styler manuals are not very brilliant when explaining the Kodak PCMS. Even the Kodak manuals for a poor job explaining that. You can find more information about the KPCMS in the Aldus or the Kodak forum or just ask your local expert <g> ana /krazy images
#88700From: Yost GroupMar 4, 1994 11:39 AM
>>Just disable gamma correction for your monitor and load the images with the default 1.8 gamma PT. Ah, but I want to be able to calibrate my monitor gamma — which is quite different from manipulating the gamma in the files. Quite simply, I want to calibrate my monitor for the software, and then have it load files without assuming any gamma curve from the file itself. I agree with you about the documentation. I'm not sure you can even find the word "gamma" in their index. It's as if they don't want to admit it exists.