nomad2
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Odd Pixels when Scanning Pictures
I purchased an Acer Prisa 310P (300x600 dpi, 30 bit, parallel) scanner. I am very happy with it, however when I scan images at 300 dpi (color photographs) I often get stray pixels of the wrong color. It is barely noticeable when you view 1:1, but when you zoom in, you can see that there is one pixel here and there that are way off, e.g.,
pink on white.
If I resample the image in Paint Shop Pro, most of the problem disappears, but I assume that this is due to the calculation of pixel color used in resampling.
I've cleaned the glass with a special cleaner for glass screens and filters, and a lint free cloth.
Is it possible that I have a setting wrong, or is it the hardware?
pink on white.
If I resample the image in Paint Shop Pro, most of the problem disappears, but I assume that this is due to the calculation of pixel color used in resampling.
I've cleaned the glass with a special cleaner for glass screens and filters, and a lint free cloth.
Is it possible that I have a setting wrong, or is it the hardware?
ASKER
This happens immediately upon scanning. Once resampled, cleaned up and saved as JPEG, the images look fine.
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ASKER
The problems appear on the "raw" scan, before any image manipulation. I tried to recreate the problem, and changed my video driver from 16 to 24 bit.
What I found was that the first scans that I did after the scanner warmed up (15 seconds) had pixels of the wrong color showing up throughout the image. Later scans were OK, regardless of the video driver settings or TWAIN driver settings.
Is it possible that the scanner requires more than the minimum warm up time to be able to correctly read full color images?
Also, for the first couple of scans, the "wrong" color pixels did not show up in the same place if the same picture was scanned twice without moving the picture on the scanner or changing any TWAIN driver settings.
What I found was that the first scans that I did after the scanner warmed up (15 seconds) had pixels of the wrong color showing up throughout the image. Later scans were OK, regardless of the video driver settings or TWAIN driver settings.
Is it possible that the scanner requires more than the minimum warm up time to be able to correctly read full color images?
Also, for the first couple of scans, the "wrong" color pixels did not show up in the same place if the same picture was scanned twice without moving the picture on the scanner or changing any TWAIN driver settings.
nomad2...
Indeed the warm up the lamp before scanning is always BETTER than the regular procedure. These lamps when warmed would read better the color tables. So it might help greatly in your case to use that feature.
We always use it for our scans to make sure that we have to best possible reading.
When you said that the pixels or the line change from one place to another is the proof that nothing is wrong with the scanner. If something was wrong it would ALWAYS appear in the same place.
Hope this clarified more, but if you require more info, just ask
Regards
Indeed the warm up the lamp before scanning is always BETTER than the regular procedure. These lamps when warmed would read better the color tables. So it might help greatly in your case to use that feature.
We always use it for our scans to make sure that we have to best possible reading.
When you said that the pixels or the line change from one place to another is the proof that nothing is wrong with the scanner. If something was wrong it would ALWAYS appear in the same place.
Hope this clarified more, but if you require more info, just ask
Regards
If this is close, I will give you some more info, 'else reject my answer and let somebody else have a go.
Stephen.