H. Simpson From United States of America, joined Mar 2001, 949 posts, RR: 2 Posted (14 years 6 months 5 days 10 hours ago) and read 1726 times:
my scanner is a HP 3200C, I scan the photo with 800dpi and the file is about a 20-something mb. I use Canon Photo Gold editor to sharpen the photo and resize to 1024*680.
The question is will the picture become sharper after I compress the photo(because I "squeeze" 800dpi)?
I still getting blurry image after I scan with 800dpi, work on it using sharpen ,brightness and compress into 1024*680 size. Why?
Screener4 From , joined Dec 1969, posts, RR:
Reply 1, posted (14 years 6 months 5 days 8 hours ago) and read 1665 times:
What is the "native" DPI of your scanner without inerpolation? I can scan at 3200 DPI if I want, but there's no point, because the scanner just invents the in-between pixels (its native resolution is 600dpi, which is typical, although there are some 1200dpi flatbed scanners now). Find out what the native res. of the scanner is and scan at that.
The picture will not be sharper just because it is smaller, but any problems (blurry, out of focus, etc.) will show up less because they aren't as big!
You will always need to apply some sharpening to the final 1024 x 680 sized image after you have resized it in order to ensure it's sharp. The trick is to apply enough to get the image sharp, without introducing "jaggies"
Sonic99 From , joined Dec 1969, posts, RR:
Reply 3, posted (14 years 6 months 4 days 10 hours ago) and read 1636 times:
Native resolution = optical resolution (normally advertised as such). Most scanners can achieve even higher resolutions than the optical capability and this is referred to as "interpolating".
Scanning at higher than optical resolution is no solution at all since this will only cause dissolution....
i.e. if you have a 600dpi scanner, then scan your photos at that resolution and try to achieve the highest pixel output you can get. Then shrink the photo to a maximum of 1024 pixels (length). Never enlarge from the output otherwise the image will be filled with "garbage" pixels.