CanoScan LiDE 100 resolution much smaller than advertised

[Stev]

I bought a CanoScan LiDE 100. While I am happy with the scanning quality, I am wondering why I can only scan as high as 600 dpi, despite the 2400x4800 dpi advertised optical scanning resolution.

This article, http://www.scantips.com/chap3c.html, seems to explain how the machine specs differ from the actual results. Here are some pertinent quotes:

"A 1200 dpi CCD sensor really cannot do anything else but scan at 1200 dpi. This rating does not mean that it can resolve 1200 lpi in a test target, but instead, the CCD simply reads 1200 samples per inch. Nyquist sampling theory says the image can never resolve more than 1/2 of that detail level, and in the real world, a little less."

"A 1200x2400 dpi unit is a 1200 dpi scanner."

By their logic, my 2400x4800 dpi scanner should be able to achieve nearly 1200 dpi, but both the Canon software and the Windows scanning software only allow 600 dpi. Do the above statements only apply to CCD scanners, not CIS scanners? I'd appreciate it if someone could set me straight here!

 

[mpilchfamily]

Are you sure your having it do a full res scan and not a simple quick scan?

 

[Zap]

Scanner manufacturers often quote a "interpolated" resolution which is not the true optical resolution.

 

[Stev]

mpilchfamily: It's a full scan.

Zap: This isn't the interpolated resolution, it's the optical resolution.

 

[frostedflakes]

I have an LiDE 30 that's rated for 1200dpi, and the Canon software lets me select resolutions up to 1200dpi.

Are you using Window's built-in scanning wizard? If so, maybe try Canon's scanning software instead.

 

[dawza]

Try it with a third-party program (i.e. Irfanview-->File-->Select TWAIN source [select the CanoScan driver, and not the WIA driver]-->Acquire/Batch Scanning).

The CanoScan Toolbox's (or whatever included program the LiDE 100 uses) resolutions are limited, but you should have full access with most third-party apps (Photoshop, Irfanview, etc).

 

[frostedflakes]

I use Canon's software (ScanGear CS) and it doesn't appear to limit anything, as I mentioned it will allow scans up to 1200dpi. Maybe it does limit resolution for certain models, though. I'm also using a very old version of the software that came with the scanner on a CD, perhaps restrictions were added in newer versions.