CompuServe Messages

[ continuation ] discontinuities in this curve result in obvious irregularities of the contract transfer function of the final image (posterization). Even your automatic gamma generating slider tool generates a choppy curve – especially in the shadows. I have written a little Basic program to generate an ASCII file with the 256 values needed in the .TFM file. It uses the following equation to manipulate 'gamma:' x = y^n/255^n-1 This results in a family of curves starting with n=1 where the equation becomes x = y (no gamma change). N can be any integer or fractional value from 1 to a practical limit of about 5. N can be empirically determined, but should be the result of measuring input densities (sample densities of the original being scanned) and output densities (samples of either the electronic image or of the finished, printed piece). This equation (or something like it) should be part of the IM user interface. Photoshop has such a tool. It is wonderful, but it is limited by the underlying limitations of Photoshop itself. IF IM had such a tool, and if the user interface were more polished, IM would surpass software on high end proprietary machines which presently cost in the $100K range! Please don't ignore our needs for better color separation software. Again IM has enormous power, which is almost impossible to use in any meaningful way. Presently, I must leave color separation of my images to Pgs or ProPage. Those programs do not allow me to control the separation process, as IM does, but they _do_ allow me to place the image on the page without losing my sanity. If I color separate the image in IM, I have four resultant files (CMYK) all of which must be placed in exact register on the page, and then grouped into a single unit. Even then, the results are unpredictable and chaotic. What we need here is a solution similar to (or exactly the same as) a de-facto standard that has developed in the MAC world. Everyone doing color separation on the Mac uses Photoshop to manipulate and color separate images (or to import [ MORE ]