NO BULL: Scan Speed Part 2
Contex define large format scanner productivity in "drawings per hour"
... Continued. [Contex Scan Speed - previous] [Contex Scan Speed - next]
What the large format scanning industry think
In preparing this article, Scanners4CAD spoke to many experienced large format specialists. All agree that one, uniform measure of rating scanning speed which can be applied comparatively to all wide format scanners is long overdue and desirable but almost all worry that Contex's attempt to present raw scan speed as a measure of "productivity" is unrealistic.
These are the views of a some key wide format scanner solutions providers.
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UK - Allied Images
Stephen Morin, managing director of Allied Images, the British Colortrac distributor, believes that the number of scans per hour which Contex is claiming seem unrealistic.
Morin says "To date the practice of specifying scanner speeds has been measured in ips (inches per second). The use of ips serves more as a means of comparing relative speeds between different scanner makes and models rather than a measure of scanning productivity.
"However, the move by Contex towards quoting the number scans per hour seems unrealistic as it requires two or more operators working without interruptions or hold-ups at an unsustainable rate. Most experienced users understand that in the real world the working environment and types of drawings being scanned do not allow the throughputs quoted being achieved.
Colortrac SmartLF Ci 40
"More importantly, in our opinion, it is how changes in factors like variation in the quality of a drawing can be quickly and effectively compensated for so as to achieve a quality scan without interrupting the flow of scanning throughput. We believe quoting the number of scans per minute would be more realistic in comparing the scan speed of a scanner. This can be easily verified and enable operators to judge how this translates to the number of scans per hour or in a day."
John Bennet, Allied Image's marketing manager, remembers "the debate about MIPS when microcomputers were introduced. It quickly became obvious that MIPS - Millions of Instructions Per Second was an accurate measure of nothing at all. MIPS very quickly became known as Meaningless Indicators of Performance. Contex's new measure strikes me as being exactly the same - I'm sure they can scan the number they're claiming but so what? In the real world, the operator - singular as almost no scanner is fed by two operators - should be checking each drawing because real documents are seldom crease free. They have dog ears, tea and coffee stains, all of which will slow down any conscientous operator."
Germany - Image Access
Image Access, the German manufacturer of the WideTEK range of large format scanners, rated "the fastest large format scanner in the world" by BERTL, has the raw speed to go head-to-head with the Contex SD Series.
But, says Thomas Ingendoh, the CEO and President of Image Access, raw scanning speed alone does not tell the user the full story. We have devoted a page to his comments and suggestions for an alternative measure of productivity.
See: Towards a new measure of wide format productivity
USA - Large Document Solutions
Colorado-based Large Document Solutions is a company focused on just that - scanners, plotters, copiers and software to meet requirements in large document environments.
Kevin Brinks, president of Large Document Solutions, says "We carry all of the major manufacturers of scanners, so when asked about the claims of some manufacturers here is what I would say.
"The manufacturers have always taken some liberties with their specifications, especially as it pertains to speed. Speed seems to be the biggest focus and yet it is the least important.
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"We sell all of the products because each brand and model has its advantages in different situations. The decision may be driven by technology (CCD vs CIS), application, required scan quality, software features, previous scanner experience, special pricing promotions, etc., but speed is rarely the deciding factor. Our opionion is that anything above 3 to 4 ips is not necessary.
"The process of scanning for archive applications is more about staging the document properly and checking the quality as you scan. So whether the scan is done at 3 ips or 12 ips is irrelevant. By scanning faster you lose potential quality and risk damage to the document. We tell prospective customers to expect an average conversion rate of around 50 to 60 "D" or "E" size documents per hour.
"I recently sent an email to some of our customers that have purchased scanners for service bureau work. They all concur that the 50 – 60 per hour was a reasonable number in the real world for black and white. Two said to expect about half that for color. One said that they have had 85/hour and another said 100/hour when they were working with perfect documents.
"So, whether a scan is performed in 5 seconds or 15 seconds is not going to matter, you will still be achiving less than 100/hour IF you are concerned about quality."
USA - Paradigm Imaging Group
Randy Geesman, President of the Californian Paradigm Imaging Group and a leading Graphtec large format distributor, dismisses Contex's new measure of productivity as "totally unrealistic".
Geesman says "336 documents per hour scanned at 200 dpi in color mode translates into less than 11 seconds per sheet, (2.24 ips), assuming the sheets are scanned in landscape mode which would be the obvious thing to do. In operating a service bureau for 20 years the highest throughput I have seen is about 175 sheets per hour and this is in B/W mode with all of the sheets being in the absolute best condition.
"The figure of 744 sheets at 200 dpi and B/W mode is not realistic either for the above reasons but also because nobody scans in B/W mode at 200 dpi any more.
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"Once you factor in reality - paper handling/document preparation (this may take as long as the actual scanning); folded, wrinkled, tightly rolled, torn and the variety of media types and drawing conditions / quality that would require changing the scanner settings - throughput in the "real world" can be as low as 50 sheets per hour, and again in the best conditions about 175 per hour (B/W mode).
"Double the scan speed (motor speed) does not translate into double the throughput. It might increase throughput by 30%. Aside from the condition of the drawings, the other major limiting factor is the Automatic Document Feeder - the person with 2 arms and legs.
"There is a very interesting video someone posted on YouTube that shows a side-by-side comparison in scan speed between the Contex SD and the Graphtec CS510 and CSX300."
(Scanners4CAD has some issues with this video. It fails to point out that Graphtec's image quality is compromised in the High Speed mode used in the video. We assume that whoever made this video scanned using true 400 dpi optical on the SD Series, thus disadvantaging the SD Series speedwise. Scanners4CAD has tested both these scanners and the results are not in line with our findings. Anyone wanting to view this YouTube video should acquaint themselves with the facts first.
To do this, see: No Bull Scanner Speed
Geesman says "It’s hard for me to defend the video because we really didn't shoot it. I don’t know for sure if there is any deception going on! I don’t think so. I do think there is absolutely a difference in throughput because the Graphtec scanner buffer in the scanner and the Contex SD Series scanners need the software to do the processing. Contex's Nextimage software is slower than Scanning Master. I basically agree with the points in the video but anyone who sees it can decide for themselves."
See: YouTube Video)
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