Scanning Negatives for the First Time

[john_r_smith]

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Folks

 

we have in the past scanned many hundreds of 35mm transparencies here at work, and there are very few problems other than dust and some increase in contrast. Just recently, though, I have had some medium format B/W negatives scanned to tiffs by a local lab, and although the results are generally OK, there sees to be a lot more grain in the sky and areas of flat tone than I would have expected from Ilford FP4 when printed in a conventional darkroom. The results are more like 400 ASA than 100. Is this a known problem with B/W neg scanning, and does the scanning process somehow accentuate the grain?

 

John

[stunsworth]

Hi John, make sure the lab aren't appling any sharpening to the scans. Gain with FP4 shouldn't be a problem, especially using MF.

[andybarton]

Also make sure they are not applying any ICE dust removal software in the scan

[strick]

Folks

 

Is this a known problem with B/W neg scanning, and does the scanning process somehow accentuate the grain?

 

John

 

Yes, it's a known problem, and yes, the scanning process accentuates the grain. The better the scanner, the more it accentuates it.

 

You surely know that you can fight this problem by using a mask for sharpening (this means, you're sharpening only the outlines of your subject, while you soft-focus the other parts of it, e. g. the grainy sky).

 

I hope you'll excuse my bad english

 

Greg

[stunsworth]

Greg, with a MF scan grain aliasing shouldn't be a problem - and I can't say I've ever found it an issue using 35mm on my Coolscan V. There's something else going on if a MF FP4 negative has excessive grain.

 

One thing to bear in mind is that if you are looking at a 100% magnification, that represents a _huge_ print, so it's not unusual to think the grain is more of an issue than it really is.

 

For example if I scan a frame of 35mm at 4000 dpi and look at that at 100% magnification, the file will be approx 6000 pixels wide. That would correspond to a print some 4 times wider than my 21 inch monitor.

[john_r_smith]

Chaps -

 

thanks for your help on this one. I have checked and there is no sharpening or dust removal on these scans, so that's a good start. And the grain does look a lot more prominent on-screen than on the ink-jet prints. Maybe I have been spoilt by the grainless super-smooth tones from the digital cameras at low ISOs

 

John