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zzfoxxx
January 6th, 2003, 06:47 PM
I have a scanner that i purchased in Feb of 2002

cost....... around 90 US

It gives exellent quality pics esp when scanning pics in quality magazines

but sometimes there are yellow diagonal lines.... maybe only faint,,,,,, but they impair the result

scanning pics on newsprint sometimes results in fine diagonal lines visible on the pic

It is still an exellent machine giving generally good results

However Im wondering....... has technology moved on....... is it worth upgrading? and if so what should I go for ?............ is there technology that can avoid these yellow lines etc ?

Thanks in advance for any advice,,,,,,,,Pete

kjanx
January 6th, 2003, 07:07 PM
those lines are put there by the owner of the photos to prevent copying.

falcon2000
January 7th, 2003, 01:02 AM
I am wonderiing may be you are seeing the moiré pattern usually seen when scanning half-tone printed matter (most magazine and news prints are half-tone.) Sometimes the moiré pattern will also appear as lines if the pattern is "strong" enough. I've seen that before for some printed materials.

Check the scanner software or the TWAIN, most scanners now have setting to use a de-screening filter to reduce the appearence of moiré pattern.

scantips.com (http://www.scantips.com/basics06.html) has an excellent explanation of this phenomenon and ways to reduce it.Originally posted by kjanx
those lines are put there by the owner of the photos to prevent copying. I highly doubt that. Although the technology does exist (for many many years now alteady) but its deployment requires printing on specialty copy-protected papers. These papers are expensive. Technologies vary but most incorporate a transparent layer invisible to naked eye which contains material that deflect scanning light from scanners and copiers such that the only thing that you will get is simply random patterns or highly distorted pictures. Ordinary newspapers and magazine will not be using these expensive papers.

photolady
January 7th, 2003, 01:20 AM
Some software like, Photodelux, has a filter to remove moiré patterns from photos.

falcon.....;)

JoJo Gunn
January 7th, 2003, 01:46 PM
XnView has a button called "reduce noise" that has helped somewhat on patterns. I use descreen on my scanner but it doesn't work 100 percent on that honeycomb smudge resistant surface stuff, for example. XnView's filter helps, but at a cost of losing some sharpness overall, so test it on a resized image, not your original.


http://www.xnview.com/

HappyFace
January 9th, 2003, 07:45 PM
If you are scanning out of magazines, even high quality ones there is no way that the photographer did that as a protection device. I am sure you are talking about moire patterns. Those patterns become more obvious when scanning lower quality printed materials. It is very tricky to remove moire patterns but it can be done. Many of the good programs have editing techniques that try to clear the pattern but the angle of the selected mask is critical and requires a good bit of experimentation. If the output quality of the edited image is not of prime importance you may find that lessening the resolution and using little or no sharpness enhancement at the time of your scan will give you a servicable picture. Do some scan experimenting with all different varieties of picture subjects from noticeably poor to very fine expensive magazines. Using a magnifying glass observe that the dot patterns are not nearly as compact on the poorer pictures as on the finer prints. Expect more moire to show up on the scans of poorer looking images. Just another reason to carefully select the input images you are selecting for scanning.

spragers2
January 13th, 2003, 05:27 PM
You could also try scanning at different resolutions, as some may make the pattern more or less noticable than others.

scarecrowdr
January 14th, 2003, 04:38 PM
A lot of Scanners have various settings for scanning....ie, magazines, photos, lineart, etc., etc.,.......i allways use Photo to get a top scan.....So if yours has it, select Photo, put some Black Card or paper behind the page you are scanning, click the moir within the twain and PreScan, if its suitable click Scan, if not then Crop etc., then Scan...You Will end up with a better scaned page.
Experiment with everything within your scanning program Twain..You cant do any Damage...
regards,
Dennis.....