When I use colour photos in documents, the whole document and PDF-file becomes very large. The photos, some times, are in 600 dpi resolution, and I have been thinking about reducing the resolution, with Bridge 6, to let say 200 dpi.
My question is: am I doing the right thing?
When I test it on a 300 dpi laser printer, I can not see any difference in output quality, but maybe it will be worse on a professional colour printer (which I do not have ).
If my way of doing it is correct, what would be a reasonable resolution to use?
I have learned in the past that with normal screens, the resolution of the photo can be 1/4 of the output resolution, which in your case could be 75 dpi. With FM-screens this should be 1/3, so 100 dpi. I would stay on the safe side with 150 or 200 dpi, because I think it also depends on how fine or coarse the screen is.
But, with a line-drawing (only black and white) you should stay with the output resolution.
I have a few CDs with so called HiRes photos and they are all 300 dpi for 'normal' sized output.
When I want a really smaller PDF, I export the document with Bridge as PS and the run it through the Distiller. This makes for smaller sizes, especially with bitmap images.