24 Apr
2015
24 Apr
'15
8:03 a.m.
On Apr 24, 2015, at 11:00 AM, js at cimmeri.com
wrote:
On 4/24/2015 9:46 AM, Paul Koning wrote:
Why don't you actually try it. Also, I'm assuming reading on a screen (where I
read most of my vintage manuals) vs. re-printing. My screen resolution is 90dpi.
Anything over that is pure waste. Maybe you have better eyes than I do, but I can't
discern image quality over 100-200dpi for printing.
You?re assuming I haven?t. In fact I have done scans for a long time, with different
resolutions; my comment was not based on ignorance. Ditto my statement about professional
printing practice. And while a lot of computers have 90 dpi screens, some (like mine)
are substantially better. Finally, depending on your eyes you might well be reading at
greater than 1:1 scale.
paul
...
I would not call 90 dpi ?good enough?. The professional printing rule of thumb is
that for an n grayscale dots per inch halftone image you need 2n DPI resolution. So 90
dpi is, at best, low grade newspaper resolution. A standard commercial grade scan for
good quality printing is 260 dpi or so ? which means 300 is certainly a fine choice. 150
or below may well be acceptable if that?s the best you can get, but you?re definitely
compromising image quality if you do that.