Impact of DPI on scan quality

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I have a lifetime's worth of Kodachromes, Ektachromes, and sundry negatives that I would like to digitize and print. Most were taken with either Leica R's or M's and I would like to keep their quality. I've seen that Nikon has announced a new series of scanners with the lower priced scanning at 2900 DPI and the more expensive at 4000. Given that my hoped for output will not exceed 11 by 14 prints - is it necessary to step up to the 4000 DPI unit?

Thanks for your advice.

-- Seth Honeyman (shoneyma@nycap.rr.com), February 13, 2001

Answers

i would say yes....

ive been printing some of my negs scanned at 2700 dpi, with an output print of around a 9 or 8 inch height or width...this roughly translates to and output dpi of 300 or so...

printing a 10 inch pic scanned from a 4000 dpi scanner will yield a 400 dpi image, which is fairly good, but might show some pixelation.

it really depends on what you are going to do with the prints and the quality you wish to have. it would be worth getting darkroom prints for the best quality.

-- grant (g4lamos@yahoo.com), February 13, 2001.


Seth:

My two cents worth... A grain of silver in film is just under 1/10,000th of an inch in diameter; or stated another way, the resolution of film is slightly better than 10,000 DPI. I think the closer your initial scan resolution is to the film itself, the happier you'll be with the results you obtain in output.

-- Jack Flesher (jbflesher@msn.com), February 14, 2001.


I've been doing all my printing with film scanner and inkjet printer for at least 6 years, and 80% of it that way for 5 years before that.

You can make beautiful prints with output dpi of 250 on a 1440 dpi inkjet printer. At 2700 ppi full frame scan, that's about an 11x17" print. Certainly a 4000 ppi scan will give you more data to work with, but I've found that it's only really necessary if you're making significantly larger prints.

Godfrey

-- Godfrey DiGiorgi (ramarren@bayarea.net), February 14, 2001.


Also, you should take a look at third party drivers for these scanners. I use the LS2000 which is rated at 2700 dpi, but if I want a really hi res scan I go to the silverfast driver which will give twice the resolution - 5400. The results are amazing seen on screen. On the other hand I don't print.

Theoretically this will give you a nearly 18" high print at 300 dpi full frame. Anything that size is going to be on the wall, i would have thought, so you won't be looking close to see the grain anyway.

There are most likely silverfast drivers for both these new scanners and they will probably be bundled with them, so that may solve your problem.

Rob.

-- Robert Appleby (laintal@tin.it), February 14, 2001.


Since it's a hypothetical question (i.e., at this point you don't really know what you're going to do with the scans, exactly) the appropriate hypothetical answer in this case would be "more is better" :-) You can always choose to drop some resolution, but you won't be able to get more if you need it.

-- Michael Darnton (mdarnton@hotmail.com), February 14, 2001.


I think that more resolution is always better. I have the Minolta Dual II (2780 dpi) and it gives excellent results up to 8 x 10 on a Epson 870 @300dpi. For color you are hard pressed to tell much difference between this and a conventional pro lab print. If you want to go bigger you need more resolution. Also one of the nice things about digital is the way you can very easily crop and you tend to do this more on screen than I used to do in the darkroom. As a result you are often wanting to blow up smaller areas to larger sizes -then you need the resolution. I think if you are seriously going to produce a lot of 11x14 prints then you need a 4000dpi scanner, if not and 8 x 10 is more your typical size then the lower res scanner will work just fine. Of course I have not said anything about Dmax.....

-- Robin Smith (smith_robin@hotmail.com), February 14, 2001.

Call some pro labs and ask what output resolution they use for digital prints. I'd be surprised if you found 300 dpi to be less than professional quality.

-- Joe Buechler (jbuechler@toad.net), February 14, 2001.

The Fujix 3000 printer I sometimes use prefers 400 dpi and will take 320 if I insist. There's no 300 input, though. My Epson wants 360. Some people say above this gives even better results, and some deny it. . . . .

-- Michael Darnton (mdarnton@hotmail.com), February 14, 2001.

I see little difference between printing at 500 dpi and 300 dpi on an Epson 870. Usually I just print at the resolution it gives with out any resampling, so it usually works out at higher than 300 as I rarely print an 8 x 10 on the printer. I will hedge my bets and say that the limiting factor in my opinion is largely the printer not the scanner and the print quality is not as good as a conventional print at close distances @ 3 inches and looking carefully. There are indeed scanning issues (retention of shadow detail etc. etc.), but there are many issues with printing in the darkroom too that can minimize your chances of getting the best possible interpretation of your image. If I had a b & w darkroom I would prefer to use that for b & w, but I don't, so 35mm digital is a close second. Sometimes coming second is not good enough - it all depends on you and your time. For 6 x 6 I still use a conventional darkroom and love the unquestioned high quality. For color I think if you want to be in control then digital is 100% easier than a conventional process.

-- Robin Smith (smith_robin@hotmail.com), February 26, 2001.

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