Vuescan - scanning resoution without scanner attached

[roger___4]

<p>I have an Epson V700 scanner attached to an old P4 computer. This works fine for batch scanning, but when I have to rescan DNG files, it becomes too slow. So for rescanning DNG I use my laptop, which doesn't have the scanner attached.</p>

<p>When I open a DNG file, the maximum preview and scanning resolution is 50dpi, while the file is scanned at 1200dpi. I want to open it in Vuescan, not in Photoshop or another program, as Vuescan handles the DNG file as if the scanner is attached - it sees no difference. I've had this problem before, and with tricks I could get it to 300dpi, but it's simply not acceptable that it works like this.</p>

<p>Is this normal behavior for Vuescan and is there a reason why it works like this, or is it a bug? Is there a way to get this working normally? Am I doing something wrong?</p>

[cabbiinc]

<p>Vuescan should be displaying the max resolution as the resolution that you've originally scanned as. So if you've scanned at 1200 dpi it should show a max of 1200 dpi. When it shows 50 dpi is the pixel dimensions still the same as the original or something much larger? If it's much larger, then check the output tab's "Printed Size" when you're doing the initial scan. Possibly setting that to "Scan Size" to see if that clears it up.</p>

<p>But I have to ask why you're bothering with DNG if you don't plan to open the file in another program? Try unchecking DNG from the output tab, rescan, and see if this helps any. DNG was only added at the request of users and the .tiff file is what the Vuescan author originally used.</p>

[roger___4]

<p>I'm scanning thousands of old slides and negatives. I tried to figure out the best way to do this, and for me that was using DNG. I create a DNG file at full size, plus a JPEG at half size for immediate use. Reading the Vuescan book it seems that Vuescan doesn't see the difference between a DNG file and when scanning via hardware. Besides that, opening a DNG is much faster than rescanning.</p>

<p>Changing the print dpi doesn't make a difference. It was set to scan size, which would be OK according to you. Setting it to manual and to 1200 dpi didn't do anything. </p>

<p>I've made a screenshot. It shows the image dpi at 1200, the preview image, and the dropdown with the dpi setting. If I set it to custom, then 300 or 600, it changes back to 50 after a moment.</p>

[steveg]

<p>You're using quite an old version of vuescan (9.0.60) it might be worth upgrading to the latest version (9.2.23) - it might be a 'feature' thats been fixed in the later version.</p>

[roger___4]

Thanks! Updating fixed the problem. I should have thought of that myself! :-)

[cabbiinc]

<p>I'm glad you've got it worked out. And I'm going to say this next more as a clarification but I'm not telling you to change your workflow, just an FYI. Vuescan can make DNG files that you can then reprocess in Vuescan, but originally the "raw" file type was the "Raw file: Tiff". It retains everything, including the IR channel which can be used or discarded just as you would at the time of scanning. DNG was added later and may be slightly different, but it looks like it's working fine for you.</p>