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elvis2010
06-08-2009, 08:50 AM
What resolution should I scan pictures at. I want to make more 4x6 prints but I would also like to be able to enlarge them to maybe 5x7 or a couple even larger.

I would also like to be able to touch up one or two of them in photoshop.

What is the best file format for these as well?

What would be the best resolutions for what I want to do. I was scanning a couple at something ridiculous like 9400 or 9600dpi last night and thought the files were way too big for what I needed to do.

Thanks

John_Reed
06-09-2009, 11:38 AM
What resolution should I scan pictures at. I want to make more 4x6 prints but I would also like to be able to enlarge them to maybe 5x7 or a couple even larger.

I would also like to be able to touch up one or two of them in photoshop.

What is the best file format for these as well?

What would be the best resolutions for what I want to do. I was scanning a couple at something ridiculous like 9400 or 9600dpi last night and thought the files were way too big for what I needed to do.

Thanks
It depends on how you will use the output image. If you're submitting photos to a print publisher, they'll generally ask for 300 dpi, so they can accommodate the necessary lithographic screens for printing images for publication. If you're going to print on your own printer, you'll want at least 150 dpi (or pixels per inch), and some would say 200, though my experience says that 150 is a good breakpoint. So for example, if you were scanning a 4X6 print with the idea of printing it at 5X7, 200 pixels/inch, you'd need 1000 X 1400 pixels, right? So you'd need to scan your 4X6 at 250 or better to yield enough pixels to get what you want.

Do NOT confuse scanning resolution with printer dot rates. If you print a 200 pixel/inch image on an inkjet printer, it may offer you 1200, 2400, or 4800 dpi. Let's consider one pixel being printed on your printer, set at 1200 dpi print resolution. So the single pixel gets presented to the print head, and the printer spits out 6 dots to complete one line of the larger pixel. :)

Dread Pirate Roberts
06-14-2009, 06:06 AM
I'd go with a simple answer. If you're scanning 4x6 prints yourself using a flatbed. Scan at 600dpi. Better to be too high a resolution than too small so you only have to do the job once.

If you're going to open them after and manipulate them in photochop then you can use TIFF format. If yu're just storing them or doing a bit of manipulation and quality is not rediculously important then just use jpg with not too much compression.

If its slides then a different answer applies.