I just uploaded a
series of test scans with my Epson V700 of a
4x5 picture of a railroad bridge, taken with my Nikkor-SW 90/4.5 at f/16 or f/22, probably f/16. This is an
exceptionally sharp lens. Hence, my tests might not be indicative, as the resolution of the 4x5 is so sharp. I've read that the 1/R formula underestimates final resolution when one component has much more resolution than another, and works best when both components of the system are of nearly the same resolution.
In any event, from my eye, at least when given a very sharp 4x5 to begin with, it seems from my scans that the V700 can produce very good 10x enlargements as seen on screen (this is about in line with estimates of the true optical resolution of the V700 being about 2400 dpi, which would suggest 8x enlargements at 300 dpi if you don't have much loss of image quality due to 1/R). But that's just from what I see; maybe those scans don't look nearly as good to you guys.
Given a negative that has exactly the same resolution as it seems the V700 has, about 2400 dpi (47 lp/mm), we can expect the final scan to be of a quality of about 23.5 lp/mm (1193.8 dpi, which can produce about a 4x enlargement, or 20x16 print). This is in line with what I've usually seen as suggested for the capabilities of the Epson V700.
Just a parenthetical note, I've seen Lenny Eiger claim that the V700 or V750 has a resolution of about 1100 dpi or something like that, and others argue that such is wrong, and the resolution is 2400 dpi. I
think I remember Lenny saying he'd seen those estimates of 1100 dpi from prints made from a V750 or V700 scanner at an Aztek lab. The preceding paragraph would explain the discrepancy between 2400 dpi and 1000 or 1100 dpi. The actual resolution of the scanner component is 2400 dpi (47 lp/mm); however, when scanning in something that is also 47 lp/mm, the 1/R law is probably pretty accurate, so final resolution drops to 23.5 lp/mm (1194 dpi). If that's the case, it explains the discrepancy between Lenny's estimates of the V700 / V750's resolution, and estimates made by others.
I will be sending another copy of the 4x5 that I scanned in to Lenny to scan in at the beginning of December (after I find out if it was accepted in a photo-show). Then I will upload a crop of the same section. If I make a print for the show, of course I'll print from the drum-scan.
Bookmarks