DIY High-Speed Book Scanner from Trash and Cheap Cameras

Step 77 Load a Book and Capture It.

Put a book under your platen, and adjust platen height where the platen attaches to the column. You want the platen to rest at the base of the binding, so that it is not pressing harder at the top of the book than the bottom. Unless all your books are the same size, you will need to adjust this for each book.

Start at the beginning of your book and work to the end.

HINT: Sometimes, I run into occasional focus issues -- you can see some of them in the tool book I scanned at the intro. One simple way to deal with these is to keep a "Focus sheet" around. It's just a piece of paper with printed words on it. If you encounter a page that has nothing in the middle for the camera to focus on, before capturing that page, stick the focus sheet over top of it and focus the camera. Remove it, and then release. You'll have a perfectly focused page.

Comments

[you1]

I'm moving my post to the Camera page, to keep my post relavant to the webpage.

When pusing the USB connection button to the two cameras:
The first push on the button causes the cameras to focuse on the pages,
and a second push on the button will capture the images.

Alternatively, holding the button down for a longer duration (aboult half a second) will refocus the cameras and then capture the images.

Question: Is it possible to capture an image on every button press (quick click) without a re-focus, and capture a re-focused image by holding the button down a bit longer (long clicks)?

For example: click, click, click, (long click for re-focused capture), repeat.

StereoDataMaker http://stereo.jpn.org/eng/sdm/quick.htm talks about Ricoh CA-1 switch unit; however, I'm not quite sure how to utilize it with the USB hub.

This addition will make capture quicker (imagine 1000+ pages); additionally, we don't have to worry about the camera not focusing properly when half the page does not have any content.

[daniel_reetz]

I have thought a lot about implementing similar behavior. But my idea was a little different. Basically, I want to have StereoDataMaker attempt focus every time, but if for some reason it can't find focus, it should revert to the previous position. I am confident this is possible with a script loaded into SDM. However, I haven't had the time to work on it at all. The Ricoh switch unit has some desirable properties, but it's not so different from the hub solution I've made.

[you1]

I created script to put the remote button on steroids :D.

Here is a link to the discussion thread: http://www.diybookscanner.org/forum/viewtopic.php?f=3&t=9&p=59#p59

Here is a link to the script:http://www.mind2b.com/component/content/article/9-info/9-multiple-camera-remote-control-button-software

Best,
Edvin

[daniel_reetz]

Totally, completely, absolutely, awesome. Can't wait to try this!!

[daniel_reetz]

By previous position, I mean previous focus position.

[bkrpr]

Also, some more information on the focus issue (from http://bkrpr.org/doku.php?id=usingpowershota590):

Important
Manual focus works wonderfully, but it is also the only setting that your camera will forget. Everything else in the Manual setting mode, the ISO, file size, etc., will remain set from session to session, but every time the camera turns off, or even goes into sleep mode or image-review mode, the manual focus will be forgotten and the camera will resort to auto focusing.

The result of this is blurry pages, but only on those pages that have little text in the center for the camera to focus on. If you notice blurry pages, especially if most of them are all on the right side, where chapter end pages often do not fill up enough of the page for auto-focus, this should be the first thing you check.

The easiest way to fix this is just to be aware of when the camera will “forget” your chosen focus and reset it. So when you turn the cameras on, set the focus, and if you take a break and let the cameras go into sleep mode or change to review mode to check a shoot, re-set the focus once you are ready to shoot again.

The camera's setting menu, available via the “menu” button next to the D-pad, will let you increase the time delay before sleep mode comes on, which should cut down the number of times you need to re-set the focus. Since checking for focus is one of the only reasons for going into review mode while shooting a book, knowing how to keep the camera set to your chosen fixed-focus setting should also eliminate most of the need to review pictures while you are shooting, in turn reducing the number of times you have to re-set the focus.

[daniel_reetz]

Excellent instructions. Thank you. I wonder if we might be able to use CHDK to wake the camera with the focus at a given position? In principle, it shouldn't change with your design, though it would with mine. I also had the idea to have a CHDK script that worked this way: If the autofocus can't find anything, it would simply revert to the previous focus. That way single pages wouldn't be any problem at all. Again, thanks. I hope to get together with your group more substantially after mid-May, when my finals are over. Your knowledge is very much appreciated.

[FutureNerd]

Could you say a little more about "start at the beginning of the book and work to the end?" Now that the book is under the platen, how do I flip the pages? Do you mean I remove the platen, flip the page, replace the platen and readjust the platen for every page in the book?

[daniel_reetz]

Sure thing.

I don't know if you can watch the first video, but it shows the scanner being run.

1. You put the book under the platen, opened to the first page of the book.

2. You press the button on the handle; the cameras take a picture of both pages. The handle is in your left hand. Your right hand is free.

3. You lift the platen with the handle, and with your free right hand you flip to the next page of the book. You set the platen back down. It is hinged, so it goes right where it should go in the center of the book.

4. You press the button on the handle; the cameras take a picture of both pages. And so on...

I think I might not have clearly communicated how the platen works. The platen is hinged at the back -- there is no adjusting to do after you set it for the first time. Have a look at step 30 -- you can see it from the side.

I hope this helps -- if it is still unclear, maybe I can make a video to better explain it. In any case, the platen is adjusted only once for each book.

Does this make more sense?