A lot has been written about scanning black and white film, and not all of it makes much sense to me. But different scanners work differently, and you need to try and find a method that works well with your negatives, then hope it continues to do so. A few months ago I replied to a query on an internet forum saying that I didn’t have problems with Newton’s rings (interference patterns with an oil on water appearance) with my negative holder – and within days was doing scans were they really were obviously apparent.
So what works for me isn’t necessarily the best approach for you. Some people like to scan things as positive rather than negative and then invert later, or to tell the scanner they are using a different media type. Others always scan in RGB then convert themselves to grey, or choose just one of the three (or four)
With my scanner and Vuescan software I find I get good results from a straightforward approach, scanning as black and white negative, 16 bit grayscale. I scan at a preview resolution of 1200dpi, which both enables me to crop precisely and also to zoom in to check sharpness. I set Vuescan to take 2 samples, which slows the scanning down but improves the scans over normal single sampling. Values higher than 2 give little if any more information but greatly slow down the scans.
On the crop tab, the vital setting is for the ‘Border’. I set it around 10 which means that I can crop images with a slight border (especially necessary when the negs are not in the carrier exactly straight and you need to rotate later in Photoshop.) The exposure and histogram then ignore a little bit around the edges of the selected area.
‘Infrared cleaning’ does not of course work with normal black and white films, but with chromogenic films it can be worth using the lowest setting. With other black and white films I use ‘grain reduction’ at the light setting. I’m not convinced it does anything, but high settings certainly lose detail.
My aim in scanning black and white film is not to get a perfect image direct from the scan, but to transfer all of the information from the negative to the scanned 16 bit file. So the vital tool is not the image preview but the histogram. Vuescan has a pretty confusing number of parameters on the Color tab when in ‘Advanced Mode’, but fortunately most don’t matter a great deal when scanning black and white.
You can play with the B/W Vendor, brand and type, but will generally find nothing that quite corresponds to the film you are scanning, and it really doesn’t matter a great deal, though you will see some changes. Similarly with the curve high and curve low, though I find values of around 0.25 and o.5 generally work well. The two vital settings are actually the black and the white point, but unfortunately setting them isn’t entirely straightforward.
In general, for most negatives I find I need to set the Black Point to zero and then use the ‘Brightness’ setting to avoid clipping the shadows. Sometimes the White Point also needs to be at zero, but more often a small value that cannot be directly set using the buttons is needed, perhaps 0.08. You can also set the needed value – at least roughly – by switching to show the ‘Graph b/w’ and sliding the right hand triangle to meet the bottom right of the curve. But mostly its the ‘Graph Image’ that you need to keep an eye on.
Sometimes when you’ve set both black and white points as above, the actual image may be too dark or two bright. You can try altering the brightness setting while keeping an eye on the Graph Image to see you are not introducing excessive clipping.
Years ago when I first bought Vuescan (having found the software that came with my Canon scanner was useless with colour negs) I had some e-mail exchanges with Ed Hamrick, the writer of Vuescan about the white point and the small problem I had with that. I don’t think I ever got him to understand my difficulty, and although the software has improved greatly and he has responded quickly to other bug reports, this hasn’t changed.
Because I scan in 16 bit, its possible to adjust the curves considerably without getting any problems in Photoshop. So altering the tones of the scan is simple. If I ever want to I can hide shadow or highlight detail. But if you don’t scan it you can’t use it.