Sunday, February 27, 2011

Technology Tuesday - Scanners

I wonder how many other posts were prompted by the Scanfest on Sunday?  We try to get some scanning done, but we spend a lot of time discussing related things!  We had over 40 people active this time.

Toward the end, there were a few of us discussing different scanners.  Someone was using a document feeder on theirs, someone else had some artifacts (errors) in their scans at high resolutions.  Some were scanning slides or negatives.  Someone had a new wide format scanner.  Several had the portable Flip Pal scanner.  We talked brands and model lines as well. 

So, what are some of the types of scanners out there, and why should I choose one type over another?  Excellent question!

Most people are familiar with the traditional flatbed scanner, where your document is laid on a glass surface, a cover lowered over that, and the scanner does the magic stuff to get your document into the computer in a graphic image format.  There are a number of choices within this type: what size of platen (glass)?  What size of the case, overall?  What scanning resolution, what lighting type?  Can it also do slides and/or negatives?  What's the overall quality of the unit?

Like most technology gadgets, many manufacturers have both a low-end consumer-grade product, and a more expensive, more feature-laden 'pro' or high-end product, and sometimes several models in each line.  The low-end models are primarily intended to compete on price, while still fulfilling the basic requirements of the product type.  High-end models have many more bells & whistles.  A basic flatbed scanner will have a platen sufficient to scan a full Letter or A4 page, will have a cathode light source, and some basic software to control it all.  Frequently the low-end devices will also have smaller cases, appealing to those with limited space.  A high-end flatbed will have a larger platen, maybe legal size or a wide format.  It may have an LED-based light source.  It will sometimes be faster.  It will likely also have built-in capability for scanning slides and/or negatives.  The unit may be physically larger than the low-end cousins.

Some scanners are part of an all-in-one device with printer, scanner and fax capabilities all in one box.  These also function as copiers.  The printer sections can be either inkjet or laser.  Inkjets will be cheaper, and have color, while the laser-based units are generally monochrome, and faster.  Some people like these all-in-one units because a single device fills many functions, and saves space in the home office.  My personal take is that these units are more finicky, and not as good a choice when multiple people must share the unit.  What's more, failure of any part pretty much means replacing the whole unit, as they're rarely repairable in any economical sense. 

An interesting scanner attachment (some have it built-in) is a document feeder.  This lets you place a stack of documents on it, and it feeds the scanner for you, allowing you to get other things done.  For uniform documents in good condition, this works pretty well.  For odd sizes, or documents with problems like dog-eared corners, creases, staples or tears, the document feeders can jam, or mishandle the document.  Sometimes this can damage the document.  For that reason, I do not recommend using them on documents that cannot be easily replaced.  They are also not useful for photographs, as they typically require feeding around rollers.  Some older photos can crack when flexing that much, and some are printed on a stock too heavy to roll.

I mentioned the Flip Pal portable scanner, and there are also other portable units.  They vary in size, but the Flip Pal will to a 10"x6" image.  Obviously that's not even a full letter page, but the small size does make the device quite portable.  Fortunately, it includes software that can stitch together multiple scanner passes to cover a larger document or photo.  This unit seems to be quite popular among genealogists on-the-go.

Software is another thing that varies with scanners.  All of them will come with driver software to allow your operating system to connect to and communicate with the scanner.  Most also include some kind of image editing software and maybe some sort of image organization software as well.  Higher-end units may also include Optical Character Recognition (OCR) software for transcribing documents to text files of various formats.

I mentioned light sources earlier.  Most typical scanners use a cold cathode tube much like a fluorescent light, similar to the backlight in many flat panel monitors and laptop screens.  Some newer scanners use white LED's for the light source, as do some newer flat panels and laptops.  Why would you choose one over the other?  Cathodes have a warm-up time, that is, they need time to stabilize their light output once turned on.  This is why many scanners make you wait to scan.  LED's are an instant-on technology, and the light output is immediately stable, requiring no warm-up time at all.  LED's also have a 50,000 hour rated life, where a cold cathode tube is frequently rated for around 5,000 hours.  5,000 hours is still many years of normal use, so may not be a big issue unless you plan to run your scanner a lot.  The biggest plus to LED's is the lack of warm-up time and stable color output.

My personal choice is a typical high-end flatbed scanner, the CanoScan 8800F.  This model has been replaced recently by the 9000F with a few enhancements to the features, but essentially the same thing.  It has LED lighting, and includes the ability to scan both slides and negatives.  It does not have a document feeder.  The platen is larger than Letter/A4 size, but not quite legal size.  It came with Photoshop Elements 5.0 for Windows (4.0 for Mac), and Omnipage LE OCR software.  It also includes Canon's MP Navigator software which includes an organizer.  The connection to my computer is USB 2.0 based, as are most scanners now.  (Older scanners used Parallel ports or SCSI, or even a proprietary interface that required installing a card in the computer!)  I would strongly recommend it as a very good all-purpose scanner.  The only possible drawback is that it's not portable at all.

What are you using to scan documents and photos?  Do you like your choice?  What would you choose differently, next time?  Discuss in the comments below!

Related posts: 
Scanning Technology
Digitizing With Cameras, Part I
Digitizing With Cameras, Part II


Tech Tuesday – Have you stumbled upon a piece of technology or new Web-based application that would be of interest to your fellow genealogy colleagues? Post at your blog on Tech Tuesday and show us the ins and outs of this technology and how it can benefit the genealogy community.  This is a new series suggested by Donna Peterson of Hanging with Donna and in the past there have been many iterations of this series: the National Archives and Records Administration (NARA) blog Narations as well as The Family Curator by Denise Levenick.  (Blurb shamelessly stolen from Thomas McEntee at Geneabloggers!)

UPDATE: Yeah, Blogger screwed up and posted this immediately even though I told it to hold it until Tuesday morning.  You get an early read, enjoy!