Digital BW, The Print

--- In DigitalBlackandWhiteThePrint@yahoogroups.com, Ross Borgida 
<borgida@y...> wrote:
> Best bet is to scan at the optical resolution..For example, the optical resolution on 
an Epson 3200 scanner is 1600 dpi..not 3200 dpi.  


Ross, your post raises several issues, one of which had not occurred to me.  Issue:  
you want to print a file to a 7600 but the image dpi, when resized to the desired print 
size, is less than 360.  From what has gone before, here and on the EpsonWideFormat 
group, I understand that the 7600 will want to print from a file at 360 dpi.

There are two obvious ways to output the file at 360 dpi.  One is to upres the file in 
Photoshop and send it to the printer as a 360 dpi file.  The other is to send the file to 
the printer at whatever dpi it is after resizing, and let the 7600 driver upres the image 
to 360 dpi.

Your post made me realize there is a third way:  Increase the scanner's resolution 
beyond its optical resolution.  If the scanner's optical resolution is 3200, but the 
driver allows scans at 6400, then one could scan at 6400 dpi, resize the image for 
printing in Photoshop, and have plenty of pixels to throw out, so you are 
downsampling to 360 dpi.

The conventional wisdom is not to scan beyond the scanner's optical resolution.  
Why?  Might it not offer a better way to meet the resolution requirements for big 
prints on the 7600/9600 than upres'ing in Photoshop, or leaving it to the printer 
driver?

Of the three solutions, which works best?  

Two more points:

Ross, you say the Epson 3200's optical resolution is 1600 dpi.  I use the 3200 for 90 
percent of my scans (a Microtek 120tf does the rest) and I've seen nothing in the 
Epson literature that suggests that the optical resolution is anything but 3200 dpi.  
Can you point me in the direction of something that supports your claim?

Second:  Several have suggested Genuine Fractals as a way to upres smaller files for 
printing.  My experience with GF is that it does no better than Photoshop in this 
regard, and the commercial imagers with whom I've spoken (such as Reed Photo, 
www.reedphoto.com) claim that in fact GF is inferior to PS.  And it's slow.  I don't 
consider it a useful solution to this problem.

Sanders McNew