On 1/25/08, olin.sane.7ia at shivers.mail0.org <olin.sane.7ia at shivers.mail0.org> wrote: > Date: Fri, 25 Jan 2008 17:09:20 -0500 > From: "m. allan noah" <kitno455 at gmail.com> > On Jan 25, 2008 4:36 PM, <olin.sane.7ia at shivers.mail0.org> wrote: > > it does not immediately hit any of our known chipset tests. that does > not mean much however, as we cant test for everything. the next steps > are to open the scanner and get some chip info, or perhaps better to > take a trace using benoit's usbsnoop on windows, and post that on the > web somewhere. perhaps someone here will recognize the protocol. > > I am loathe to open the thing up, since I might end up returning it to Newegg. > It looks like I am stuck using this scanner through a vmware WinXP.
no- if you can get a usb trace under windows, someone might recognise the protocol. > to that end, i would personally buy a refurbished Fujitsu fi-5220C, > ($1009 at pcnation.com). Fujitsu has been reasonable about providing > documentation to me, and has kept the protocol of their larger > machines pretty much the same for years. Something similar can be said > for Epson, though they seem to have more new machines with an unknown > protocol as of late. HP particularly is quite bad about changing > protocol with every single model. > > Great, this is a useful bit of intelligence for someone new to the > scanning-in-linux scene: Fujitsu products are the linux-friendly ones, yes? > (Perhaps there should be a list on the sane-project.org web pages saying > which scanners and companies work well with sane.) well, i dont know that i would sane 'linux-friendly' about Fujitsu, i just have sources where i can get docs, as opposed to Canon and HP who have both given me the runaround for months in the past. I am sure that other sane devels could recommend a company that has given them some support, i can only speak to the ones i know. > While I'm writing, I discovered something else I didn't know about sub-$1000 > scanners today. I thought the automatic document-feeders on these flatbed > scanners would work by feeding the document onto the glass, where it would > then be scanned in the standard flatbed way, by waving the scanner bar across > the bed. But that's not what seems to happen. What happens is that the the > scanner bar sits at the ADF end of the flatbed, and each page of the document > is fed past the bar in a tight U. yes- your suggested method would take twice as long, and getting the paper off the flatbed is hard with variable sized documents, you would need a huge belt and a long output tray, and the belt would abrade the glass. Now, the cheapo ADF mechanism seems > very unlikely to have the kind of precision registration that the scanner > bar tracking mechanism would have, so I'm guessing that ADF-scanned documents > would come out lower quality than documents scanned by laying each sheet down > on the flatbed by hand. if you want edge registration, you have to use a flatbed, or you need to use a scanner with a black background and overscan capability, and some deskew/cropping software to clean it up. other than skewing issues, the quality of a good adf will look no different from the flatbed. just beware of the 'U' being too tight for the thickness/print of your media. > Am I right? > > If I am, what do you have to pay to get up to the class of machine whose ADF > works by positioning each page on the flatbed? Is that done? i've never seen a machine (other than a big copier/scanner combo) that does this. i prefer the paper path in most adf-only machines, since the 'U' is often pretty straight. flat-beds with good quality are very inexpensive. the combination machines just are not as popular, so cost more. perhaps you would be better off with two machines. > Is this issue related to the ultrasound-sensor stuff that Fujitsu brags about > for their scanners, whatever that is? nope- that is double-feed detection. senses a change in the thickness of the paper. their less expensive machines use IR instead. > Is there a place on the web where I could learn more about these issues? sure- the as-yet unwritten webpage you make which documents your experiences looking for a machine :) allan -- "The truth is an offense, but not a sin"
