As you know, CCD-based scanners differ from models with a CIS array in having a bigger depth resolution. This property helps to achieve a sharp image in the centerfold of a thick book or a magazine which in its turn guarantees that the OCR program gets all the symbols right. Another application of this property is to “photograph” volumetric objects, for example PCBs of electronic devices, complex relief objects, etc. In fact, the user can create a photo-collage right on the scanner’s glass. To check this property I put a few pens on the bed of the CanoScan 5200F and scanned them. Here’s the result:
Well, scanning such objects is rather a purely theoretical test. Let’s see what we have with standard originals.
Since the CanoScan 5200F features Canon’s FARE Level 2 technology, its ability to process transparent originals needs to be checked first. It’s not the scanning proper but the post-processing of the scans in an image-editing application that usually takes most of your time, so a dust-removal technology should be most helpful, if it works right. I used a slide of a KODAK Ektachrome Professional Film Q-60E3 target as the reference sample of a transparent original. I didn’t deliberately put more dust on the film – there’s enough of it flying about in our test lab.
The first scan shows you the image as it is – with all the dust speckles.
The second scan is free from dust. To give you a real-life example, I also scanned an old photograph with FARE Level 2 technology turned on and off.
You can clearly see the dust on this photograph fragment
Reduce Dust and Scratches enabled: no trace of dust on the fragment