Grain in scanned images

There has been an interesting discussion on comp.periphs.scanners recently about scanners, film grain, noise and aliasing. I wondered why my 2400dpi scanner produces very grainy scans in comparison with prints (and the scanned images are of much worse quality than pictures from my 2Mpix camera because of the grain) and why the grain is more visible in dark areas. Now it’s more clear to me (I hope), especially thanks to the Web page mentioned in the discussion. Basically, grain doesn’t match well with digital technologies and you need a very high resolution device to cope with it.

Epson devices on Linux

I’ve added information on running the Epson Perfection 2480 Photo scanner and Epson Stylus Photo R220 printer on Linux to my small Linux hardware page.

If you find those small pages useful, please consider sharing pieces of your knowledge on Internet as well, it can help to many people. My Linux hardware pages are almost the only pages visited on my site, they are visited mostly by people looking at Google for information on running something on Linux, so people need this kind of information. I’m going to write more on the topic of sharing knowledge on Internet sometimes.

Trouble with printing

Today I had to print something. My aging DeskJet refused to print it in sufficient quality again. I had to use another printer connected to a Windows machine. That meant an interesting challenge to print a Czech document on Windows. 1.1.3 PDF export produced a document with Czech characters missing. This can be fixed by printing the document into PostScript and converting it to PDF. Such a PDF looks well in xpdf but not so in Acrobat on Windows, which can’t display Czech characters in it correctly. Fortunately, PDF export in 2 beta seems to be fixed so after two hours of hardware and software experiments I was finally able to print the document.

That story encouraged me to buy a new printer. About a year ago I considered buying Epson R200, but I got discouraged because of very expensive ink and paper. Today, there is Epson R220 available, it’s a bit cheaper than R200 was last year and the ink and paper seem to get cheaper as well. I need new printer anyway, so I’ll give it a try. HP is out of question, all HP devices I tried to use have suffered from some troubles so far. Low-end Canon printers may be more economic, with less clogging troubles and with a better text printing quality when compared to Epson. But unlike Epson, Canon seems to be careless about Linux drivers thus their devices are completely useless to me. Epson printers are well supported on Linux and I’ve already got good experiences with two Epson scanners on Linux, so Epson is where I’m going to spend my inkjet money.