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tjhaefner
26-Nov-2006, 14:24
Although I have a Epson 4990, I'm not that thrilled with the scan quality for my 4x5 negs.

Q: has anyone done comparison scans of best printing for optimal scans (for instance, paper texture, contrast, etc)?

Thanks--perhaps this question has been asked before, but I cant seem to find it in all the posts.

robc
26-Nov-2006, 14:35
the best print surface for scanning from is high gloss. Any matt paper will reflect light in many more directions than a high gloss paper. That is why high gloss prints have a greater apparent dmax.

Tim Lookingbill
26-Nov-2006, 15:51
You should be getting excellent scans off your 4990 Epson. However I know negatives can be a challenge on any scanner because of how the scanner software deals with orange mask and image inversion.

I found a way to get better scans of negatives of any size or brand by forcing EpsonScan to output linearized data or as it appears in the input histogram. I posted to another forum just today. I'll post it here and see if it helps you...

"Thought I'ld share a method for getting good negative scans I stumbled upon recently playing around with EpsonScan settings on my 4870 flatbed that noticeably reduced grain/noise and increased shadow detail and dynamic range. It also creates scans with smoother transitions and texturally more realistic scene depictions.

In a nutshell it's making EpsonScan output the same SHAPED RGB histograms as they appear in the input graph which is mainly influenced by whatever the orange mask filter and image inversion is being applied internaly to produce the preview. Because of this and the nature of negatives the input histograms don't always produce a linear capture indicated by having all three RGB input histograms line up on top of each other. Getting it on output is almost impossible. Choosing No Color Correction will not produce this on output either.

The important thing is getting this input data to be unmanipulated or more linearized with the least amount of compression/expansion to the input data on output using EpsonScan tools. You can get very close with the least amount editing by first setting Configuration Color Control gamma to 3.0 assuming a 2.2 gamma calibrated display is used. Then click Auto Exposure to get EpsonScan to update its internal settings and then click reset.

This usually creates an input composite histogram close to the middle of the graph producing a very flat and washed out preview with the blue channel being the most compressed due to the internal orange mask filtering. This bright washed out look has the added advantage of allowing you to see shadow detail that would otherwise be compressed into black using any other gamma setting.

You can now start out improving upon and linearizing the output relying strictly on the look of the histograms and applying small tweaks to the input only endpoint sliders on each RGB channel and the middle slider on mainly the blue channel to get them to all line up and roughly have the same shape between each channel. Once there it's just a matter of applying a simple correction curve locking down 250RGB highlite region and adjusting saturation in EpsonScan. This method produces a noticeably robust capture and wall to wall tapered endpoint histograms viewed in PS. Save the settings and apply to other frames of the same film type.

Although this seems tedious, going the quick route by clicking for neutrals within the image using Epson's B/W and neutral pipettes is like applying a sledgehammer to the data as will any other Auto setting producing subpar output histograms and previews. The above method produces far superior results."