Archived posting to the Leica Users Group, 2007/08/18
[Author Prev] [Author Next] [Thread Prev] [Thread Next] [Author Index] [Topic Index] [Home] [Search]Larry, Even with my ancient Konica Minolta Dimage Scan Dual II, Tri-X scans better than the other B&W films that I have used. I see no problems, but I am only scanning at 2820, not 4000. Jim Nichols Tullahoma, TN USA ----- Original Message ----- From: "Lawrence Zeitlin" <lrzeitlin@optonline.net> To: <lug@leica-users.org> Sent: Saturday, August 18, 2007 9:50 AM Subject: [Leica] Re: Scanning Tri-X > On another list someone complained about the "posterization" and aliasing > encountered in scanning Tri-X film. Here is the quote: > > "both my 2880ppi and 4000ppi > film scanners posterize my Tri-X negatives... which > makes sense. there is also nothing you can do to > remove sampling errors after you scan. My early > analysis of Tri-X grain showed that it has strong > frequency content around 4000ppi so when my scanners > sample at around half the Nyquist frequency the > aliasing is just a fact of life. With finer grained > films, the grain is still aliased, BUT since the > signal to noise ratio is so much higher the actual > useful *image* data is not lost and *luckily* the new > aliased *grain*, while not an accurate representation > of the original, is still aesthetically pleasing." > > Can someone explain what he means in plain language? I've scanned > hundreds of Tri-X negatives with my Minolta Dimage 5400 scanner at > 4000ppi, and, apart from the inevitable dust spots on poorly stored > negatives, I have yet to see what he means. If there is a problem, is the > scanner software correcting it automatically? > > Larry Z > > > > > _______________________________________________ > Leica Users Group. > See http://leica-users.org/mailman/listinfo/lug for more information >