Hi Mark-heaps, These files have all been saved in PS. For some history, this started a few years ago, it's been a long time, but it's a thing that sometimes really really gets to me. It happened at the same time that the icon preview in the title bar turned into a generic blank icon (not just for tifs but all files). Apple blamed it on Adobe, and Adobe blamed it on apple, and after a couple of years the subject went away. This is why I'm asking here again. And I wonder if others have seen it. It happens on 5 machines in my office, so surely I can't be the only one. To answer your question: Tifs are generally 8 bit, and I do recognize that changing a graphic file from 8 bit to 16 bit does in fact cause preview issues, especially for files over 500mb. I can live with that, although seriously, 16 bit image files have been around for decades now. So, all files are created in PS, although I've saved files in GIMP after making a non destructive change to see if that makes a difference, and although the icon preview may come back, and often does, after some time it will revert to a generic icon. It's as if the OS is generating the icon every time you open the directories, so even fixing them isn't permanent. I think the one common denominator is that all the tif files are large. I have a 4x5 scanback camera that generates very large files, and final flattened files will be from 200MB to 1.xGB. Although generally in the 200 to 500 mb range. Mostly 8bit in their final form. And all files live in the Adobe 1998 color space. Every single file in question is generated like this: Mac Pro, garbage can model 2013, 3.5GHz 6-core Xeon, 64GB RAM, 18666 DDR3, 2x AMD FirePro D700 6144MB 4x5 scanback camera outputs Tif file at 16 bit with custom camera profile file is edited PS CC, converted to Adobe 1998 color space, pared to 8bit, saved @ 300ppi at the original size of artwork photographed Saving options "image previews: always save checked: Thumbnail checked"
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