Epson 1640xl sharpness problems

[glazer]

I have been struggling with sharpness problems with my 1640XL.
Have already done a lot of scanning with the scanner, but am still not happy with the results.

I have played with the focus in between 2 and 2.5 with negs in the holders. There doesn't seem to be a way to scan them film and get the grain optically.

Resorting to Unsharp Masking is not a good option, as that method has produced noticable ugly patterns (I have a good eye for this, as I also own a drum scanner and know what great scans shoudl look like). Even with conservative settings llike 50% and .5 radius. So, I do not want to have to use unsharp mask to 'bring back' focus the scanner can't get.

Is the flatbed CCD technology simply not there yet in terms of optical sharpness?

I read a couple of other posts regarding focusng problems, so this seems to be a software issue, as one fellow found that scanning with the TWAIN produced sharper scans.

I am using 5.52 AI

Thanks

[President_LSI]

SilverFast with Expression 1640XL & optical sharpness/grain

First of all you have to understand that a flatbed scanner does not have the crisp optical sharpness for film that a dedicated film scanner such as a Nikon LS4000 or a Polaroid SS4000 has got.

Nevertheless you should get decent results with your Expression 1640 XL, when you adjust the focus (you can manually adjust the focus in SilverFast and see the results in apreview window, do not just use the preset focus) and use the USM (Unsharp Masking dialog) accordingly.

You cannot get the grain optically because there is so much depth of focus with that scanner. For that reason SilverFast Ai 6 (among other powerful enhancements) has a sophisticated grain filter.

TWAIN is not a good solution as it has no proper integration into colour mangement and ICC.

Look at the new features of SilverFast 6 here:
https://www.silverfast.com/highlights/v6all/en.html

You can also read the review by Ian lyons on SilverFast Ai 6:
http://www.computer-darkroom.com/sfastv ... astv61.htm

[glazer]

A follow up to my previous post:

I performed a bunch of tests today, and after comparing the results, I have concluded that not only is there an underlying problem with the image quality with the Epson, but the unsharp masking brings it right out.
This happened in photoshop's USM as well.

However, doing multiple passes helped somewhat.
What really made the difference, was simply scanning at the optical resolution. The resulting file size is slightly smaller than my client wants, but it is sharper.

The result? I will scan at 1600 dpiu at 100% with no sharpening, and no sharpening in photoshop afterwards.
Compared to the scans that were 300dpi at like 500% (which, it turns out, were scnaning at 3600dpi and then interpolated back down to 1800dpi), it is a smarter workflow.
I am not used to lower end scanners like this, and was caught off guard. Should have known better.
And if the client wants 'sharper' I will perhaps do multiple pass scanning with slight USM.

Have other people seen the ugly pixel patterns after sharpening a scan from one of these things?

[President_LSI]

Pixel Patterns with Epson Expression 1640XL

These pixel patterns result from the hardware interpolation of the Epson scanner that is on by default. Please go to "Options" in SilverFast and select under "General" --> Interpolation -->Anti Aliased and should should not have those pixel patterns anymore!

[glazer]

thanks for posting so fast.

I do have Anti Aliased selected. The only other choice is Silverfast Standard.

Perhaps this is a bug in the software that is not blocking the Epson scanner's defaults?

Furthermore, since I have decided to scan at optical resolution only, those patterns shouldn't be caused by interpolation, no?

[bear]

I have noticed the same thing with the Epson scanner, not as sharp as I hoped. The USM goes along way in helping.

mark

[sfbodega]

Hello,

I can really relate to the issues previously mentioned in this exchange, though it is now 2 years later! I am used to drum quality scans, and am finding the results of the 1640XL with SF 6.2.1r9 on Mac OS 10.3.5 to be less than desirable. The Epson Scan Photoshop plugin results in sharper and smoother scans, though the interface is extremely basic and limiting.

My main issues are a general lack of focus as well as posterization and stairstepping mainly in the midtones and shadows. I am adjusting my focus (tried all options) and results are still very soft. I prefer not to apply USM at the scan level, though it seems to help the scan appear more in focus.

However, the posterization/stairstepping issue is a constant problem, and I am hoping that someone will have a suggestion on how to resolve this. I am not using any of the auto features, and am applying only minimal curve adjustments to my images.

Thanks, Carolyn