Soft scans - due to improper control of v700 dual lens?

[Brad Farnsworth]

I have been using the Epson Scan software to obtain scans from a v700. I have obtained scans that show detail to about 50 lp/mm, well in line with the ~2200..2800 dpi resolution reported by other users.

I recently started using the Silverfast SE software because I want images in 48-bit format. The scans I obtained at 2400 dpi are dreadfully soft -- just plain out of focus. Resolution is perhaps 30 lp/mm. So I rechecked the system with Epson Scan and again obtained the sharper 50 lp/mm image. Aside from the scan software, nothing else changed or was moved.

So I went back to the Silverfast and tried other options to isolate the problem. I tried HDR vs. 24-bit color vs. 16-bit gray -- all still soft. Then I tried changing the scan resolution to 4800 dpi. That fixed it! At this setting the scans are as sharp as the ones I obtained using Epson Scan at 2400.

It looks to me that the dual lens control for the v700 is activated in Silverfast by the choice of scan resolution. This would seem not to be the Epson's intended mode of operation, as the choice of lens is not a function of resolution (after all, there would be little harm in using the sharper lens for lower resolution scans) but of the height of the scanned material (at glass or elevated in a holder).

I would hope that Silverfast does not force you to scan at 4800 to get 2400-quality results, especially given the additional time and disk space that would impose.

Has this been observed (and resolved) by anyone else? Am I using the Silverfast application incorrectly, or overlooking another control that would fix the focus? Or is this possibly something that should be changed in the Silverfast software?

[LSI_Heidorn]

Dear Brad,
this sound strange, could you please report it to our Web Form, so our Testers will try to verify it ?

Greetings,

Nils Heidorn

[pknouf]

Nils Heidorn,

I am having a similar problem with my new Epson V750 Pro. If I use Epson scan and set the 4x5 holder at the + or 3.5 mm setting for the height adjusters, I receive the best quality scan possible, as contrasted to the same software and the holder height at the 0 or 3.0 mm or the 2.5 mm height. However, when I use Silver Fast AI Studio with the scanner, the best, but lower resolution as compared to the best Epson Scanner software scan results, is obtained when the 4x5 is placed on the scanner glass. It appears that your software is causing the Epson Scanner to use the lense for reflective scans as that setting for the scanner uses the lense that focuses just above the scanner glass rather than the second lense which should focus most sharply at about 3.5 mm above the scanner glass. What are the settings I should use in Silver Fast AI to cause the V750 Pro to use the second lense? Is this a bug in version 6.8.1r.1a

Thanks,

Phil Knouf

[LSI_Heidorn]

Dear all,
as this seems not to be a singled out thing, i forwarded this to our bug testing team directly, lets see if we can verify your problems !

Greetings,

Nils Heidorn

[pknouf]

Nils,

I am not so sure that this is a bug. Perhaps we should look at the installation of the software. Are there any log files or configuration settings I should look at or are these questions better responded to my your support staff? It seems quite apparent to me that the scanner is being directed by the software to use the wrong lense, hence the out of focus result.

Thanks for your help!

Phil Knouf

[pknouf]

I am troubled by the delay in answering my posts to this forum. I have not heard back for my post to the support folks either. Is this usual or just because of the August holiday?

I would like to be able to use the SilverFast software but for now it is useless. Is there a return policy if necessary?

[LSI_Heidorn]

Dear Phil,
i rechecked, i *did* forward your bug and a link to theses posts to test & support.
Of course holidays delay work, but is has only been 4 work days since i did so.
The priority that is given to a bug is strongly attached to the number of people experiencing it and the effect that it has on the user.
While you certainly cannot work as long as your images are too soft, it seems that not many Users are having this trouble because we are not flooded with similar remarks.

So please give it some more time before my colleagues can check on this.

Greetings,

Nils Heidorn

[LSI_Noack]

Dear Phil

as explained in your support request ticket, I unfortunately failed to receive another request by you before the one from the 20th, which had been addressed on the 20th, too.

Dear users of the Epson (Perfection) V700/V750/GT-X900

Epsonscan knows two settings: scanning with filmholder and scanning with area guide.
SilverFasts equivalents are: scanning transparency and scanning transparency (whole flatbed).
The scanner has two different fix focus settings, and it uses one of them for filmholder scanning, the other if the object is placed directly on the flatbed glass.
Thus if you are using the "wrong" (with respect to how your images are placed onto the scanner) mode, you'll experience de-focussed scans.

Other the other hand, you can set resolution options of 2400 or 4800 or else. SilverFast doesn't use a certain focus settings in fixed combination with a given resolution, which had been suggested in a prior posting. Instead it is possible to scan on both "focus levels" with either resolution, depending on which scan mode ("Transparency" vs "Transpareny (whole area)") had been chosen.

While the scanner does feature a very high resolution for a flatbed device, it depth of field/sharpness is rather small, so it is easy to get unfocussed/blurry scans if the inappropriate mode is used for scanning the image.
Furthermore, the images themselves could placed an obstacle to optimal focussing, e.g. think of slides in thin or think plastic slide frames. That's why Epson introduced those small plastic clips with the film holders of the V700/V750/GT-X900 series, which weren't featured with models published earlier.

By the way, it is necessary to distinguish between impression of "sharpness" due to focus, impression of "sharpness" due to higher or lower image detail caused by different image resolution, impression of "sharpness" due to sharpen filters, impression of "sharpness" due to comparing different parts in the image that might be not of the same sharpness/crispness in the original already, and impression of "sharpness" because of different contrast in the scans generated.

In this topic we had been discussing scanner focus options, and resolution.
It had been suggested that SilverFast would combine different focus settings based on resolution - which would be incorrect if it actual does.
I had tests run on both, Windows and Mac versions of SilverFast 6.5.1r1a, but the results do not support that claim. Instead, SilverFast - correctly - addressed the focus setting via the scan mode.

To addressed the sub-point raised concerning scanning speed:
In my opinion, scanning at 4800 dpi makes little sense with regard of generating more image detail with this scanner. Most if not all 2400 dpi scans will give no less information in the resulting image, let you work faster with them, and - if that's necessary for the final printout - could be rescaled lateron anyway.
However, there are always other points that could be made for scanning at a higher res, e.g. rescaling a 4800 dpi image to 2400 dpi instead of scanning 2400 dpi originally will reduce noise in the image, but will on the other hand pose more problems to infrared image defects correction.
But that is a complete different story I don't see further need of discussing here.

Best regards
Sonny Noack
- Manager Technical Support, LaserSoft Imaging AG -