Digital BW, The Print

This subject seems to come round constantly but each time I think I  
am getting a grasp of the concepts for scanning and printing, someone  
says something new which fills me with doubt and, if like me you are  
getting a once only opportunity to scan pictures for archiving and  
printing, where small detail can be important, I get worried that I  
am not hitting the right spot between economy of space and hedging my  
bets for future printing capabilities.

For example, I am currently scanning black and white extracts from  
images and negatives which are at a crop size of about 3" x 2".  I  
want to be able to print these at razor sharp optimum at A4 size but  
I keep being told that between 200 dpi and 300dpi will be fine and I  
have done many already heeding this advice and am happy to note the  
files are not at all huge. I use VueScan which computes the  
resolution based on a comparison of the original to the desired print  
size and I can't help feeling that the prints may not be as crisp as  
they could be. There does not seem to be a VueScan forum or indeed  
any VueScan support, so whenever I see people discussing these issues  
I get twitchy and start asking questions. So sorry if I seem to be  
taking this a bit off topic.

My main printers are 360 machines but I would like to think that when  
the time comes and capabilities improve I will have scans which can  
fully exploit the raised printing standard. On the other hand, I can  
see there are physical limitations to the human eye. I would like to  
be able to apply the 10" viewing rule to A3 images but do not want to  
flip the other way and end up with massive files which take an  
eternity to scan.

Presumably there is an equation which can work back from a printing  
optimum but I remain confused.  if I could be guided to a definitive  
resource of comforting information, I would be very grateful

:0]

Thanks

Drew


On 13 Mar 2006, at 11:36, Bob Frost wrote:

> Bert,
>
> Roger Clark and others could tell the difference between 300 and  
> 600ppi in
> blind tests:-
>
> http://www.clarkvision.com/imagedetail/printer-ppi/index.html
>
> and he puts the resolution of the human eye at between 700-1000 ppi
>
> http://www.clarkvision.com/imagedetail/printer-ppi/
>
> Printing with a 2200/2100 at 2880 can certainly resolve lines at  
> 600 per
> inch, but if you haven't got 20/20 eyesight, you won't see all the  
> detail.
>
> Bob Frost.