Hi Speed Scanning ??

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Dear Forum

I have a need of scanning loads and loads of text material (B&W) Which is the fastest way that I can manage the rate at which it will arrive to me. Should I scan ? Should I take digital photographs ? What will be the costs of each solution? What is the fastest scanner like ? How many pages per minute ? Cost ? I need something which can do batch processing ? Thanks a lot Forum.

-- Abhijit Bhattacharjee (abhijit8086@yahoo.com), January 16, 2000

Answers

The best is a scanner with a document feeder. I don't think a digital camera will have the resolution for what you want. The speed of a scanner depends on the resolution and the size of the image, If you can automate the task, you don't need to watch it. Try an HP 6250 or equivalent

-- jonathan ratzlaff (jonathanr@clrtech.bc.ca), January 16, 2000.

Your Computer and amount of memory will have a big, big effect on the speed of any scanner you attach to it, especially if you need to do fairly hi-res scans for OCR. I would say that 128 megabytes is the very minimum for reasonable scan speed on a PC. CPU speed will come into play for OCR, but a Pentium 233MHz or above should be fast enough.

Also, a lot of scanning programs don't delete previous scans or edits from their "cache", and so get slower and slower the more scans you do at a session. (Yes Photoshop, you are guilty!) The only way round this is to shut down the application from time to time, and then re-start it.

Regards,

-- Pete Andrews (p.l.andrews@bham.ac.uk), January 17, 2000.


If you are concerned about speed and cost, and if you need readable but not necessarily high-quality images, the answer to your question is a digital camera like the Toshiba PDR-M4.

People can talk about scanning, but no reasonable setup can rival the speed of a camera with USB, mounted on a copy stand. I've been using exactly that setup for two months now and my workers can shoot nearly 4000 frames on a good day, if the originals are uniformly sized and organized well. Even with normal document handling problems, they average 3000 sheets per day.

It's important to note that the images are easily readable, but they are NOT good enough for OCR conversion. So if you hope to reduce the information to ASCII, the scanner approach is right. But if the material isn't all that sharp to begin with, the losses from a digital camera are not important.

The PDR-M4 is my choice because:

1) It has adequate resolution. ("1200x1600" which really means 600x800 genuine pixels.)

2) The shot-to-shot cycle time is around 2 seconds. The Casio Q2000UX (or something like that) is comparable. Other cameras on the market often have 10 or even 30 second delays between shots, once the buffer is full.

3) It's cheap! Around $400 these days.

Keep in mind are that the image quality is never going to be better than mediocre, you'll need a copy stand with lighting for best results, and the whole thing only makes sense if you have thousands or tens of thousands of images.

I'd be happy to provide more details. I've shot 60,000 frames so far.

-mark grebner

-- Mark Grebner (Mark@Grebner.com), January 20, 2000.


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