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How to select a document imaging scanner

By Ray Griffiths

ray@documentimagingnews.com

www.documentimagingnews.com

Here is a process to help you  determine which scanner to buy.  Choosing the wrong scanner has been the downfall of many document imaging systems.  There are 5 questions you need to answer that will guide you to the right choice. 

1. Which scanner manufactures have service in your area?
1. This is the most important question.  To many times companies go to the internet and buy a scanner without checking on local service availability.  Long term success of your system depends on the quality of images going into your document imaging system.  You will not be able to maintain quality if you cannot get the scanner serviced.  You should be willing to spend a few more dollars locally in order to get good service.
   

2. What documents are going to be scanned?
1. Make an inventory of documents that are going to be scanned.  You need to have a sample of each type of document and determine what features the scanner will need to scan each type of document.

                                                               i.      Can an automated document feeder be used?

                                                             ii.      What is the minimum and maximum size of documents the ADF will accommodate?

                                                            iii.      Does a flatbed have to be used?

                                                           iv.      Are there two sided documents?

                                                             v.      Are there different sizes of documents?

                                                           vi.      Is color important?

                                                          vii.      Is there shading?

                                                        viii.      What is the quality of the documents?

                                                           ix.      What is the issue if a document gets damaged in the scanner?

3. What is the daily volume of document to be scanned?
1. Daily volume has to be evaluated in conjunction with the information gathered in question 2.
   

2. Some manufactures put a ratting on their scanners called “daily duty cycle”.  This is stated in the number of scans per day for which the scanner is designed. Stating the obvious, you need to select a scanner that will handle your volume.  But, there is more to it than that.  For example, in accounts payable you may be scanning 1500 invoice pages per day that are generally 8.5 by 11 and can be fed though the ADF at the rate of 600 per hour. (See below about stated scan rate vs. actual through put)  But, you may also be scanning 1000 expense report documents that can only be scanned at the rate of 200 documents per hour.  Therefore it is important to know what documents you will be scanning so you can make some judgments on time required to scan.
   

3. Manufactures rate scanners based on documents scanned per minute.  This rating is only useful because it gives you an idea how fast each scan occurs.  The actual through put for scanners in an accounts payable environment will usually be less than half of the rated speed.  For example, one of the most popular scanners on the market has “daily duty cycle” of 2500 documents.  The rated speed for the scanner is 49 pages per minute.  That means in 52 minutes of scanning you will have exceeded the 2500 “daily duty cycle”.   Obviously that does not happen.  In accounts payable the average scan rate is between 13 and 20 page per minute using a scanner rated at least 40 pages per minute.  Experience has shown that scanner operators in an accounts payable environment cannot take advantage of higher speed scanners.  On the other hand scanners slower than 30 pages per minute will reduce that average scan rate 8 to 12 scans per minute.
   

4. Accounts receivable proof of deliveries can usually be scanned faster than accounts payable documents.  POD’s are the same size and the ones in poor shape can be removed so that the majority of POD’s can be scanned at close to the scanner speed rating.
   

4. Central vs. departmental scanning
1. This will determine what the duty life cycle of the scanner should be. The higher the duty life cycle the higher the cost for the scanner. In addition feature set needed maybe different.
   

2. A strong recommendation is that if more than one department is going to be using imaging system and the volume is more than 3000 documents you should have at least 2 scanners. The reasons are:
   

                                                               i.      Built in redundancy

                                                             ii.      Scanners with different features

5. Chose a scanner manufacture that supports image enhancement.  Kofax’s VRS is, in this writer’s opinion, is the cream of the crop and works on a wide range of scanners.
1. VRS is software that was developed by Kofax.  It function is to look at each image and to make it the best image possible with out operator intervention.  VRS will speed up the scanning process and improve the quality of images in the system.
   

Scanning resolution for most business applications are either 200 or 300 dpi. With today’s technology scanning at 300 dpi is usually not necessary.  In applications where documents will pass through an OCR engine 300 dpi might give better OCR results.

Many of the new scanners are duplex scanners (scans both sides at once). If you have documents that are printed on both sides you will want to get a duplex scanner.  How you use duplex scanning will depend on the volume of double sided pages.  You can always scan everything duplex and use blank page removal.

“Can we use our Multi Function Device to do our scanning?”   Answer: Not a good idea.

There are two reasons:

1.      MFDs where not designed as production scanners so the scanning productivity will be significantly lower.

2.      MFDs are mostly used as copy machines or network printers.  While it is being used as a scanner it is off line for other functions.

Answer all the questions above that pertain to your situation.  This will give you the specifications for your scanner.  Give this to the scanner vendor that you found locally and have them tell you what model scanner will work for you. Or send the results to editor@documentimagingnews.com  and we will send you some recommendations.

Here is a list of the major scanner manufactures: