> And I found, to my horror, that when my lab did drum scans of a B&W > 4x5 neg for me, they gave me my 100 meg file -- in RGB. Thus wasting > 2/3 of it. Imbeciles. David This is exactly the stupid waste of disk space most digital cameras provide their owners with. The original CCD sensor's pixels are either R, G or B ... but they interpolate up to RGB (thereby trebling the data size) before use. Of course, there are good practical reasons why this is needed for compression algorithms, but it illustrates a point that "file size & data size are not 1 to 1 with the real information content. Of course, Canon, Nikon etc enable RAW on thier high-end cameras ... sadly embedding it in a proprietory format which handcuffs the user to thier own software to use it. The most stupid of all (Was it a Fuji camera) was where the makers claimed thier CCD was "better" than other CCD designs so upsampled from the number of pixels giving really bloated files - but it made those that had mentally linked file-size to quality think they were getting a better result. In your RGB scans, if the drum scanner scans truly in RG and B, you may have been given more info than had they "desatted" for you first. You get to choose how you combine the channels. Bob
