Get a FREE fully-working copy of Steganos Security Suite 7 (worth £49.99) when you sign up to the Practical PC Newsletter. Good Scanning Starts Here - Part 1
How do I get the best from my scanner?
If you've bought a flatbed scanner, whether it connects to your PC via the parallel port, a dedicated expansion card, or via a SCSI host adapter, there are some fairly easy things you can do to make sure you get the best out of it.
One of the most regular glitches users come across is that when they come to print out a picture they have scanned, the colours aren't the same - they're close, but not the same. So how do you go about rectifying this?
It's actually quite easy, whether your scanner/printer comes with calibration utilities or not.
Here are the simple steps.
1: Open up the graphics package you use most often - there's usually one bundled with the scanner, and quite often one bundled with the printer.
2: Create a new document (File,New) of any size - up to a full A4 page.
3: Using the circles tool, draw some filled circles in the following colours: Cyan, Magenta, Yellow, Red, Green, Blue and Black. These six colours and black are usually the first on the colour picker list if there's a palette view in your software.
4: Print out your graphic onto your colour printer using the best quality paper you have, and save the document - call it Calib.bmp or whatever.
5: THIS STEP IS VITAL. Let the document dry properly - it doesn't take long.
6: Now you need to scan your newly printed document. Because you have printed what your printer thinks is pure Cyan, Magenta and Yellow (as well as Red, Green and Blue) your scanner is going to read the pure colours - and each of the six colours has a bearing on the various settings you can apply to either your scanning application or your printer calibration.
I'll take a short pause here to make a point. When you make alterations to settings, you should do so only to one device - either the printer or the scanner, but not both.
7: Now that you have scanned the printed document, print it out, allow it to dry, and compare it with your original printout. You can now make alterations to either the printer settings or the scanner settings. If the Cyan is too dark, for instance, but the Yellow is right and the Magenta is right, then run through the Scanning application to find a curve function that will allow you to change the relative brightness of the three main channels (they will be either CYM or RGB). The screen shot shows the Philips scan software's curve function, with the Red channel selected - you can fiddle with these settings until things look closer to being right.
If the new settings are not spot on, go back to step 4 and follow the loop through until your printed output matches what you've scanned. At this point, your scanner and printer are synchronised - you have successfully calibrated your printer to your scanner. Now read on!
Part 3 Scanning from Magazines
