What's The Deal?
There are a whole lot of things that are worth talking about but don't seem to have enough substance to them to justify a full-out article and up until now, we just kind of blew past these little tidbits, interesting though they may be. As it turns out, some of these tidbits keep coming back and smacking us in the face as relevant or somehow worth mentioning, so we are going to try something a bit different here. These Ramblings are going to be a regular effort where we lump some of these tidbits together, throw them at the wall and see what sticks. If it turns out there is nothing else to be said about a particular topic, then we will just leave it alone and move on. If, however, it turns out that the feedback justifies more coverage, we will look at giving that topic its very own article, ripe for the readin'.
Understand here that these Ramblings are from the warped mind of this writer alone, and may not necessarily gel with those of others on the FiringSquad staff, or conclusions reached in other articles. These thoughts, opinions and ideas are designed to be independent of the more in-depth articles and reviews that this site does, and may end up being more reactionary than normal articles would be. Some may well be of the off-the-cuff, first impression variety, while others may have a bit more thought behind them. It's up to you to decide that, but you should know up front that these are opinions, not reviews.
Scanners and SCSI
There are two main types of scanners, differentiated by the type of optical image sensor used. The primary sensors available in consumer scanners are CCD and CIS. Those with a CCD sensor, or Charge Coupled Device, use a cold cathode (or other) light source and glass lens to focus reflected light onto CCD arrays. Dedicated CCD assemblies can take up quite a bit of space and may sometimes fall out of alignment if the unit is bounced around a bit, but they are time tested and usually provide a very high level of clarity and visual quality. The second type of sensor system used today is the CIS, or Contact Image Sensor. CIS sensors are highly integrated chipsets created primarily to help save costs and bring low cost, low profile scanners to a typically higher end market. CIS sensors place all needed system components, including an amplifier, directly into the sensor IC. These smaller CIS sensors use low cost LEDs as their light source, with a prism converging the LED light. CID systems use less power and fewer parts, and are as a result, less expensive and much smaller than a CCD sensor, but CID systems produce lower quality scans. For example, scans made with CCD scanners tend to have more 'warmth' and more realistic colors with none of the 'pale noise' CID sensors often introduce. In addition, CCD sensors currently offer higher resolution that CID. CID sensor units may get better in time, but for now, a CCD sensor is the best option. If at all possible, purchase a scanner with a CCD sensor.
As for interfaces, I used to be a SCSI jockey, but that was before USB. If you are getting a scanner, I think USB gives you the best of both worlds. First, you don't have to hassle with termination, which has historically been enough to set novices on their ear. Second, you don't have to mess with expensive external SCSI cables, which can run between $40 and $100 depending on the type of card and scanner you have. Third, most modern ATX motherboards have USB built in and they already take up an IRQ, so why bother plugging in a SCSI card that may take up another one or two of those precious resources? I had the Adaptec 2940 U/W NE card, and it rocked, as long as you did not mind paying through the nose for shielded cables, spending 30 minutes figuring out SCSI ID settings and termination for all your devices, and making sure you have all the right internal cables for your internal drive. Really, I think SCSI has just outlived its usefulness on the client side, and it's time to just put that dog to rest. USB 2.0 and Firewire give us all the speed we need, at much less cost.