How to Rate a Scanner Using the Scanner Value Price Index

With close to 70 different scanners on the market today, it is a challenge to decide which large-format scanner is right for you. Until now there has been no standardized way to evaluate a scanner’s performance and to make comparisons easy across models and scanner brands.

Four Fundamental Factors

The Value Price Index that I have developed is based on five fundamental factors of a large-format scanner:

è                 Scanning quality

è                 Scanning performance

è                 Price

è                 Maximum scanning width

è                 Warranty length

The last three are tangible factors that you can easily determine by researching scanner models on the Internet. It’s much more difficult to ascertain the first two factors. How do you measure scanning quality and scanning performance? 

 Scanning quality is the hardest one to qualify as information about a scanner’s quality is not available through the scanner manufacturers, and unfortunately there’s little independent research that measures scanner quality. Despite this, we need a way to create our scanner value index and the best available method is to analyze the optical resolution of a scanner.

 Scanner performance is easier to deal with because you can find scanning speed information from scanner manufacturer’s specifications that state the scanning black and white speed and color speed in inches per seconds (ips). However, we must make some adjustments in order to use that metric to take in account an end user’s perspective. As discussed in the article:
 “How Much Speed Do You Need” (Cadalyst, September 22, 2006, http://management.cadalyst.com/cadman/article/articleDetail.jsp?id=374252), a doubling of black and white performance numbers does not lead to a double in real life production throughput. The same is observed for color scanning but here the lack of throughput is contributed mostly by the bottleneck from a computer’s scanner interface, harddrive and image processing that’s unable to handle the amount of color data transmitted from the scanner to the PC. This bottleneck comes into play when dealing with color scans above 0.5ips at 400dpi. To reflect this discrepancy, the color scanning speed should be adjusted using an logarithm to flatten out the color performance and black and white performance.  This works well based on these observations.

 The scanning width and price is still the most used selection criteria for a scanner purchase. The scanning width is obvious and hard to compromise, as you need a scanner with a scan width that matches the maximum width of your drawings, maps and documents.

 The price can be negotiable between you and the scanner dealer. In today’s highly competitive market, the price is always a winning factor. It therefore makes sense that price is measured up against the value of a scanner expressed with the scan width, scan quality and scanning performance.

Introducing the Scanner Value Price Index

The four factors that determine the Value Price Index reflect my recommendations in the “no-spin” Scanner Buyers Guide you can find at www.TheOtherSolutions.com/Wfs/All/Buyers.htm on how to select you next scanner. The Value Price Index adds a single number enabling better comparisons and initial selection of your next scanner.

Comparing the Numbers

Let’s see how the numbers stack up. I will analyze GTCO Calcomp’s scanner series as an example with its 36”, 42” and 54” wide scanners. 

How to Use the Value Price Index

Take for example the LF742 and compare it with the LF942 also a 42” scanner. The only difference is the color speed and the price; quality and all other specifications are identical. The LF742 ends up with an 9.6 Value Price Index while the LF942 ends up with a lower 7.3 Value Price Index which indicates that you are paying a premium for a faster color speed, for example $6,000 for a modest increase in color speed. Unless you absolutely need the higher color speed, you get more value for your money choosing a LF742 over a LF942 scanner.

 Let’s say that you need a 42” scanner LF942, but wonder if you spend the extra money for the larger 54” scanner LF954. The two scanner models differ only in the scan width and price. The scanning speed and quality is exactly the same. The price difference is $7,000 -- is the extra scan width is worth the $7,000 increase in price tag? The Value Price Index drops from 7.3 for the 42” model to 5.9 for the 54” model, indicating that you’re paying a premium price for getting an extra foot of scan width.

 In another example, let’s compare resolution. You are deciding between a LF436 priced at $10,900 and the LF936 priced at $16,900. The less expensive LF436 has a higher Value Price Index than the LF936 indicating that you should go with the LF436. However, the optical resolution of the LF436 is 200dpi compared to the 508dpi for the LF936. The 200dpi for the LF436 may not be enough for your needs, particularly if you work in CAD, the graphic arts or photo arenas. Even though the LF936 has a lower Value Price Index, your minimum quality resolution needs may disqualify that model in favor of the LF936 model.

Tools for Decisions

Although not a bulletproof index, the Value Price Index can be helpful as a tool to help you narrow your search of a scanner and can easily be used across scanner brands to help you compare basic value and price. This index also gives you an idea of what kind of premium you are paying when selecting one brand over another. I use the Index as one of my scanner selection tool sets at www.TheOtherSolutions.com/Wfs/All/Narrow.htm where you can compare various scanner brands against each other or between different models of the same brand.