Ideal density for scanning

[ryanmills]

Using vuescan. I am going in circles with my v700 scanner. I have found scanning with the exposure locked at 1 seems to work ok then I use levels in photoshop to tweak. However no matter how "dense" it never seems ideal. If I make them dense enough to have to crank up the exposure the photo is flat middle gray even with dynamic lighting, if I drop it back it always seems to end up under exposed. Are there any guidelines to making the ideal density? feel like i'm playing battleship looking for it and im loosing.

[Ken Lee]

"Are there any guidelines to making the ideal density? "

http://www.kenleegallery.com/images/forum/EpsonV700StepWedge.jpg

I scanned a Stouffer Step Wedge with a V700 a while back (Using the EPSON Scan software) and according to the above test the scanner is capable of around 16 steps, or 8 stops, which is 256 levels, or in log 10 terms, 2.4

This suggests that to scan the highlights of our negatives we need to develop them to a Dmax of less than 2.4, which we do for B&W generally anyhow.

It also suggests that a good scan of some color slides is out of reach, because the Dmax of slides can exceed log 3.0.

On transparency material - as with digital images - if the high values are blown, nothing is going to bring them back. With negatives (color or b&w) a better scanner or a darkroom print can often rescue the high values and penetrate excess density, but we can't restore shadow details that aren't there.

(I did not repeat the test with Vuescan, since I prefer the Epson software when using the Epson scanner.)

You might find this article helpful: Scanning Tips with EPSON and Vuescan Software (http://www.kenleegallery.com/html/tech/scanning.php).