Re: -Gallery X - (and a new question at the bottom)

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: Now, this brings me to a new question. (The first of more to come now I
have my brand new XP.) Earlier, Emily said I should not scan photos at
'more' than 800 dpi.      My question is:
:
: How low (dpi) can I scan in the photos and still get a good print?


you have to think FIRST of what size you want the prints to be, assuming a
print resolution of 300 pixels per inch (ppi)

then multiply 300x the size you want to tell you how many pixels you need
to start with

so 5x7 = 1500 x 2100

8x10 = 2400x3000

16x20= 4800 x 6000

now we head to the scanner..

forgive me but I've not followed the thread so I'm not sure what format
you've used so I'll assume 35mm which is 24mm (call it an inch) x 36mm (1
1/2")

so for the 5x7 you need to scan at 1500 dpi (really ppi)
the 8x10 needs 2400 dpi (2500 to be precise*)
the 16x20 = 4800 dpi (5000 precisely)

*assumption of 1" for 24mm is just a guide - 25/24 =  1.041667


if you'd shot with 6x6 then you would need to scan at the following
resolutions:

5x7 = 666ppi
8x10 = 1067ppi
16x20= 2133ppi

you can always scan at HALF these resolutions then upsize using a GOOD
algorithym (use irfanview) but you'd actually be sticking in interpolated
data that wasn't in the original shot.

karl





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