Ulvar From , joined Dec 1969, posts, RR: Posted (11 years 10 months 1 week 3 days 14 hours ago) and read 1150 times:
This might have been discussed before
My question is after I have scanned a slide it might be 2500x (something, bright and shinning) one step is to resize it to some where between 1280 and 1024. When I do that in PSP 7.0 I usually receives a picture where the text on the aircraft gets odd (hard to explain) but the pixels around registration and other places gets blurry, but in the original scan its looks stunning and clear.
Is there any software out there not messing up the pixels during resize? or am I doing something wrong, or is it no way around ?
Have Photoshop 6.0 and PSP 7.0 + GIMP installed, is one of this better then the other when resizing.
Hias From Germany, joined Sep 2000, 349 posts, RR: 14 Reply 1, posted (11 years 10 months 1 week 3 days 12 hours ago) and read 1083 times:
try to scan the picture with less resolution (let's say about 1300 dpi) and you won't have to resize it, if your scanner can do this.
I am also using PSP 7.0 and I am scanning my slides with it. After scanning I first crop them, resize them, then brighten it a little bit and last but not least use the "sharpen" twice. When you are using "sharpen more" it will get too grainy. That works ! I don't have any rejection because of the image quality.
Jwenting From Netherlands, joined Apr 2001, 10213 posts, RR: 21 Reply 3, posted (11 years 10 months 1 week 3 days 11 hours ago) and read 1068 times:
Another tip I've found is to always scan at a real multiple of the size you want. So if you want a 1024 px wide image, scan at 1024, 2048, 4096, etc. pixels wide and not at e.g. 2589 (or whatever other value).
This is supposed to prevent the software from interpolating between pixels when resizing to the final image size.
Ckw From UK - England, joined Aug 2010, 545 posts, RR: 17 Reply 4, posted (11 years 10 months 1 week 3 days 11 hours ago) and read 1067 times:
I always scan at the max res my scanner is capable of and use this file for post-processing. When I am happy with the file I resample down to 1024 pixels. I then use unsharp mask to sharpen the image up again. In theory, working with exact ratios when resampling should help in quality, however, when using Photopaint I haven't noticed this providing any visible improvement, though the fact that I am starting with very large files may have something to do with this.
Ckw From UK - England, joined Aug 2010, 545 posts, RR: 17 Reply 7, posted (11 years 10 months 1 week 2 days 9 hours ago) and read 1032 times:
You may or may not want to apply unsharp mask before resizing, depending on the output from the scanner. If it looks soft, I'm inclined to do so, since I "archive" my original scans for possible printing etc.
Following resizing you will always need to apply unsharp mask whether or not you sharpened prior to resizing. What might differ is the amount required, depending on how much was applied initially and the degree of resampling.
My experiments would suggest that there is no particular advantage to sharpening before resampling if you are only interested in the final version - indeed, sharpening twice increases the risk of generating unatural looking fringes, jaggies and other horrors.