Given all being equal, which is the most easily and accuratly scanned by a FILM (not flatbed)scanner, negatives or slides? I have used "negative" film, B&W and color, for years but now have a digital darkroom, therefore my question.

-- Richard Hoag (wpcdallas@aol.com), March 07, 2002

Answers

I've scanned both quite a bit. They scan relatively similarly in terms of ease and accuracy, with the exception below. There is more information on negatives and I find it far easier to get a wide range from them. On the other hand, negative scans can vary depending on the software. Silverfast 5.5 does a phenomenal job with negative scanning.

The exception is Kodachrome. I have never gotten the kind of scan out of Kodachrome that I would like.

-- Jeff Spirer (jeff@spirer.com), March 07, 2002.

If by "accurate" you mean true to the original film, chromes will be easier for the scanner operator to compare back to for scan accuracy. Not all film scanners deal well with negatives, but that situation is improving. But, one must remember that the dynamic range of even the best scanners falls short of the range in the film, so it's always a compromise.

-- Ralph Barker (rbarker@pacbell.net), March 07, 2002.

One thing I've noticed with my scanner is that scans of negatives usually results in "grainier" images than a lab print of the same negative. Results with slides are smoother.

Also, I can get a decent scan of any b&w film over about ISO 400--the scans look terrible compared to a darkroom print.

-- Mike Dixon (mike@mikedixonphotography.com), March 07, 2002.

It depends more on the particular film, scanner and software. With my old HP Photosmart, Vuescan is a big help getting good scans. Provia 100F and most color neg films scan well. Kodachrome is difficult to scan because it has much brighter highlights and deeper shadows than other films. I've gotten some good scans from Kodachrome but to get the most out of this film a drum scan is best.

-- Douglas Herr (telyt@earthlink.net), March 07, 2002.

regarding "grainier" scans than dkroom prints

The "grain" in scans, especially from desktop (rather than drum) scanners is usually due to noise from the CCD.

For example, high rez scans (10x8) from Supra 100 C41 film show a lot of "grain", and yet traditional chemical enlargements can go out to 16 x 20 with this film before the real grain is visible.

-- Andrew Nemeth (azn@nemeng.com), March 07, 2002.

Thanks for the info, Andrew.

There was a typo in my original answer; it should read:

"Also, I can't get a decent scan of any b&w film over about ISO 400--the scans look terrible compared to a darkroom print."

-- Mike Dixon (mike@mikedixonphotography.com), March 07, 2002.

The "grain" in scans, especially from desktop (rather than drum) scanners is usually due to noise from the CCD

I don't believe this is true in higher quality desktop film scanners. The problem is primarily grain aliasing, which results not from CCD noise but from fairly complicated issues related to sampling frequency. A good discussion can be found here.

-- Jeff Spirer (jeff@spirer.com), March 07, 2002.

There's a slight misalignment in the link above, you need to scroll up to the beginning of the deep blue section to get to the beginning.

-- Jeff Spirer (jeff@spirer.com), March 07, 2002.

The link shown is a good discussion of what's going on. A more practical way of understanding the effect of scanning near to the resolution of the film comes from trying to make a nice print on you inkjet printer and then copying it using a laser copier. The result is just garbage. But if you printed on a 300 dpi laser printer (not as good an image) and then copied, the copy would be very like the original. Likewise, the scanner can double the 'grain' size if it 'sees' a grain in two adjacent pixels. Setting the scan resolution higher or lower than the value which gives the 'bad' results will improve the grain in the scanned image.

I use a Nikon 4000 ED scanner and seldom, if ever, scan at less than the maximum resolution for just this same reason. At 4000 dpi I get pretty much of an image of the grain of the film (for fast fillms) and no 'clumping' effect that produces artificial grain.

Note: if your scanner has Digital Ice technology and you are using it to correct negative defects for black and white films, the results will be uniformly terrible for any silver based black and white film. The software is seeing the silver grains as defects and trying to correct them out of the image entirely. You can get a workable image under these circumstances but you'll have to distort all of the parameters controlling the scanner out of all reason. Best to turn all that off and fix the image manually in Photoshop. ;-}

-- James Schenken (jds@ifx.net), March 14, 2002.

Richard:

I am in rough agreement with the previous answers.

I spent 5 years going crazy trying to get really good scans from negatives (Nikon Coolscan scanners). Slides worked beautifully, and I kept trying to find a B&W slide film just o solve my scanning problems (no luck!) I was getting my best B&W scans from Velvia (!!)

My main problem was that negs (color & B&W both) tended to scan with very washed-out mid-tones and highlights, and messing about with the curve(s) in PhotoShop to darken them just screwed up the tonal relationships (a posterized look).

But in the past couple of years I have finally gotten quite good scans from negs. Two things helped: 1) Leica lenses (no joke! they lay down a richer tonal range) and 2) I discovered a "gamma" control in Nikon's scanning window (NOT the same thing as Adobe's Gamma screen-gamma control panel). By setting a scanner gamma of 1 or so for negs, and 2.2 or so for slides (on a scale of .8 to 2.9), I can pull more tonal range out of negs' highlights and slides' shadows.

Other scanning software no doubt have equivalent controls - in the Nikon case they were hidden away in a pull-down menu and not mentioned much in the documentation.

That being said - slides are still a little easier because, as mentioned by others, they give you a standard, especially for balancing color. There's no way to tell, by looking at a color negative, exactly what shade of red or green or whatever something should be, but this is easy to do with a slide.

OTOH, color negative usually has a slightly longer tonal range to work with (at least for me - my slide film is contrasty Velvia).

At this point I shoot B&W neg because I can process it myself easily and quickly at any time day or night, and color slides for easier editing - and find scanning both to be relatively and similarly easy (or difficult).

An offshoot - I've noticed, with MY scanner/computer/Gamma setup, that Kodak COLOR NEGS scan more easily than Fuji's. The raw scan from Kodak is already almost dead on, while the Fuji scans come in with substantial color casts that need correcting. This is not to "dis" Fuji - it just means that YOU may also get easier/better scans with one film over another, simply because they are more/less compatible with YOUR set-up.

-- Andy Piper (apidens@denver.infi.net), March 14, 2002.