Book scanner with digital cameras

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Hello, everybody, this is Jack, from Stoke. I'm new here and I know absolutely nothing about photography. (I don't even own a cheap digital camera, that's how little I know.) I have a project in mind, which you have probably guessed by the title of this thread, and I wanted to see if somebody could help me with a few questions which are probably very basic to most of you. I haven't even started building the scanner, but I can anticipate a few problems on the photography side of it:

*GLARE: The book will lie open at 90 degrees on a wooden cradle and will be pressed against the cradle by a plexiglass platen which will flatten the pages. I can imagine the plexiglass will reflect some of the light. I can also imagine there must be some lighting techniques to avoid this problem that some of you know...

*POWER: This may be a very silly question, but as I said before I know nil about this subject. Can a cheap compact digital camera be connected to the mains, just like a laptop can, rather than rely on batteries for power? I wouldn't want to have to change batteries for two cameras every few hundred shots. If only some of them can, which models or makes?

*AUTOMATION: Can a compact digital camera be controlled or preprogrammed from a PC to shoot at regular time intervals? Or even better, can the shooting be triggered by some sort of sensor, a light sensor for example? Once again, if only some of them can, which makes or models?

*KEYSTONING: In order to minimise keystoning I would have to place the camera as far as possible from the book pages and then zoom into the image, right? Would this cause a noticeable reduction in the quality of the image?

Thanks in advance,
Jack
 
I'm quite familiar with real book scanners costing tens of thousands of pounds and generally what you are paying for is high reliability, consistancy, build quality, ease of use/setup/size support / good post processing software etc etc.

Compared to just using some digital cameras setup at a page, the end result will be comparable in a lot of cases for most purposes. Especially for the home user etc.

This was the best guide for a while

http://www.instructables.com/id/DIY-High-Speed-Book-Scanner-from-Trash-and-Cheap-C/

looks like it's spawned a whole website http://www.diybookscanner.org/

In general though:
Glare - you can get anti glare coated glass (not sure on plexi) but by taking care to adjust your light source you can get away with it in general. For best results you want to eliminate shadows as well as glare so soft diffusion or just getting the angle right can work.

For black and white text scanning a lot can be fixed in PP, but for colour scans, consistent controlled lighting is required.

POWER. Yes definately for canons (e.g. G10) you can plug them into DC power. And can probably get adapters for many more.
AUTOMATION. Again I think the canons are best in this area. You an even download customised firmwares which help out ( http://chdk.wikia.com/wiki/CHDK )

KEYSTONING: Different lenses will have different characteristics, but in general you shouldn't notice any reduction in quality by zooming in a bit to remove distortion. It may also be beneficial to allow for fine tuning of framing.

If you find a nice free/cheap bit of software that can 'de-curve' images I would be very interested.
 
Hi ectp,
thanks for your help. I'm very surprised that apparently the only way to automatise or preprogram camera shooting is by using open-source software developed by volunteers and that can be used only with a particular make of cameras (CHDK + Canon). I really thought this would be sorted by now, but I was obviously wrong. A few models from other makes can be triggered with a shutter release cable and switch, but it seems it's only the expensive models, and even among them there doesn't seem to be a standard. Even Sony uses different cables for different models. So there are two solutions: Canon + CHDK or an expensive DSLR with a shutter release switch that can be hacked and connected to an Arduino or PIC microcontroller.

Glare coated glass: where do I get it from? What name does it go by? A search on eBay returned 0 results.

What exactly is soft diffusion? Remember I know absolutely nothing about photography.

"For colour scans, consistent controlled lighting is required." How do I do this?

As for your dewarping or dekeystoning tool, I imagine you're familiar with ScanTailor (the developer is an active member of diybookscanner, he goes by the alias of tulon). I've tried the latest beta version and I'm not getting good results at the moment, but ScanTailor is a very neat piece of software, so I imagine that tulon is pretty good, and he might pull a good-quality version of ScanTailor with dewarping capabilities in the next few months. I think I remember some diybookscanner members using Adobe Lightroom for dekeystoning, but I'm not sure now.
 
Hi


I expect you could get coated glass from a glazier. But I don't think it's strictly needed if you take care with your lighting


I just mean regarding the lights you don't want to be beside eg a window as the light will change. Don't work beside a door way that let's light in when people go through etc


A diffused light means you will have soft shadows and a hard light gives crispy shadows. You ideally want no shadows, or soft ones. Hard ones look bad and cause processing problems


Im not familiar with the software as I only found that site after your post and we use commercial products to do the processing.

There is a Linux script call unpaper which gives nice results and imagemagick has excellent scripting and image manipulation support.
 
To add I'd also be wary of using dslr to capture pages as they are only rated for a couple hundred thousand actuations - depending what you want to scan this could be a limit or not.
 
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