On 17 Dec 2002 at 20:18, Alin Flaider wrote: > Strictly theoretically speaking, a 4800 dpi is only capable of > accurately sampling 47 lines per mm. This is derived from > Nyquist's sampling theorem, according to which you can only sample > half the frequency of the sampling machine: > 4800 dpi / 2 / 2 dots per line / 25.4 mm/inch = 47 lines per mm > Of course in the real world you can get better or worse than that, > depending on how the sensor array aligns with the film pattern. > But to get the maximum of a 100 ASA film that usually peaks above > 50 lpm at 1.6:1 contrast degree, you obviously need more than > 4800 dpi.
Agreed, there are several films that I have scanned at 4000dpi that reveal a deal more detail under a microscope at 40x magnification. I doubt however that there is a great impetus for manufacturers of consumer scanners to produce machines capable of greater than 4000dpi resolution. Check out the Imacon site, you might be able to pic one up on eBay cheap, see: http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=2074387396 Cheers, Rob Studdert HURSTVILLE AUSTRALIA Tel +61-2-9554-4110 UTC(GMT) +10 Hours [EMAIL PROTECTED] http://members.ozemail.com.au/~distudio/publications.html
