On 09/06/2007 [EMAIL PROTECTED] wrote: > This conflicts with > claims that it is beneficial to scan at 4000 dpi or higher > resolutions. Am I likely seeing the limitations of the optics of > my scanner rather than of the information capacity of the film? > Anybody know how well the optics of the Polaroid SprintScan 4000 > compares with those of Konica-Minolta or Nikon scanners?
The main issue with scanning at lower than 4000ppi is grain aliasing on some materials (grain sizes near the Nyquist limit cause aliasing artifacts which look like exaggerated and false-colour grain). This isn't totally avoided in 4,000ppi+ scanners and Nikons have always seemed more prone due to the semi-collimated LED lightsource. Nikon 2700ppi models were especially prone, and most claims to see ISO100 grain in scans were nothing more than visible grain aliasing. I've only seen it twice with Polaroid 4000, in some overexposed Fuji200 col neg and in TMax3200. There is nothing you can usefully do with such images. I can't answer your optics question; all seem at least adequate. And normalising the images via bicubic resampling means all bets are off regarding a meaningful comparison - it's useful but it's not very kind to image detail. -- Regards Tony Sleep http://tonysleep.co.uk ---------------------------------------------------------------------------------------- Unsubscribe by mail to [EMAIL PROTECTED], with 'unsubscribe filmscanners' or 'unsubscribe filmscanners_digest' (as appropriate) in the message title or body