Archived posting to the Leica Users Group, 2001/12/19
[Author Prev] [Author Next] [Thread Prev] [Thread Next] [Author Index] [Topic Index] [Home] [Search]Tim, Is this only a problem with slides? I assume that this is not a problem with negatives. Thank you, Sam Krneta - -----Original Message----- From: owner-leica-users@mejac.palo-alto.ca.us [mailto:owner-leica-users@mejac.palo-alto.ca.us] On Behalf Of Tim Atherton Sent: Wednesday, December 19, 2001 11:46 AM To: leica-users@mejac.palo-alto.ca.us Subject: RE: [Leica] Film scanner recommendations. Here is just one post on the discussion of this problem with Nikon scanners - it is also a problem I've noticed with Nikons. It is apparently a depth of field problem due to the lenses Nikon uses. It's a fairly commonly acknowledged and oft discussed problem. Ed Hamrick who makes the Vuescan software has had to spend a good deal of time figuring out how to set up the focussing to cope with this. Tim A > -----Original Message----- > From: owner-filmscanners@halftone.co.uk > Subject: Re: filmscanners: Canon 4000 scanner VS Nikon LS4000 > > > Greetings all-- > > I'm a bit surprised to see the nature of the comments about reports of focus problems; > as if this is a new and unheard > of issue. Surely anyone who's been on this list awhile is aware that > this is a perennial issue with the Nikon filmscanners! > > Web reviews that mention focus problems with the Nikon filmscanners > that I've learned about through this list include: > > http://members.austarmetro.com.au/~julian/ls2000-focus.htm > > http://www.pytlowany.com/nikontest.html > > I also reported here my own experiences with my two-month old Nikon > LS4000ED only a few weeks ago, complaining about focus problems. Let > me reiterate: > > o I have thousands of Kodachrome slides dating back twenty years in > both plastic and cardboard mounts with what I consider "normal" > degrees of curvature for slides. > > o I have a number of these slides where the Nikon cannot produce > sharp scans across the entire image. > > o The NikonScan software lets me place the focus point anywhere on > the image I like, and will give me razor sharp scans at that point. > However other regions of the image will consequently become blurry. > > o When you manually set the focus point (by clicking the preview > image where you want the scanner to focus), the scanner will focus at > that point and report a number. By clicking around you can compare > the various focus numbers. > > o Regions that are within 6 focus units of the focus point (the > scanner just gives a number, doesn't say whether this represents > microns, angstroms, or what) will be substantially as sharp as at the > focus point. > > o Regions that are 12 units different from the focus point will be > noticeably blurry. > > o I have some slides where I have measured a range of at least 20 > focus units. On these slides I can click various areas to find the > range of focus units, set the scanner manually at a number halfway > in-between, and get the best AVERAGE sharpness across the image. > HOWEVER, the blurriest parts are blurrier than when I scan the same > slide with my 4-year-old 2300 dpi filmscanner. > > o Therefore on these slides I'm getting 4000 dpi sharpness in certain > parts of the scan (say the center) and less than 2300 dpi sharpness > in other parts (say the edges). > > o I have not done as much work with negative strips as I have with > slides. I do see some focus variation across negative images but so > far it doesn't seem as bad as for my most-curved slides. > - -- To unsubscribe, see http://mejac.palo-alto.ca.us/leica-users/unsub.html - -- To unsubscribe, see http://mejac.palo-alto.ca.us/leica-users/unsub.html