ChrisLilley: many thanks for taking the time to explain the correct way to sharpen in LAB. Unfortunately I don't have Photoshop; I currently use Elements8 which does not appear to have LAB, and GIMP which, although it does have LAB, is strictly 8-bit. I'll save your helpful post in case I upgrade in the future.
Pau: thanks again for the helpful comments. I surmise then that I'm OK with the current setup (except for the severe cropping), especially that you had earlier remarked that (except for color) my photo of the diatom was good for a 40x 0.65 NA objective.
Rashid
my first post
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