Moved to Origami Scanner- a folding book scanner
Platen/ Cradel angles
A responce to spamsickle, thanks for the feedback! Could you please define Keystoning, just to make sure I understand, and describe the reason it happens? I believe I already understand but I am so new to this yet that I may be mistaken. Both the platen and the cradle are inherently adjustable in this design. I see the default setting to be 90 degrees on both so the cameras would be at a default of 45 degrees as I understand. The lighting overhead in the previously mentioned light hat. The adjustable nature of the entire project is to allow folding not particularly to experiment with alternative set ups. The ability to do alternative angles is just a happenstance. What could that ability help one do?
Input on the best way to build a portable scanner
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- ceeann1
- Posts: 106
- Joined: 17 Nov 2010, 20:00
- E-book readers owned: Several Palm PDA's
- Number of books owned: 700
- Location: Albuquerque, New Mexico
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Re: Input on the best way to build a portable scanner
Last edited by ceeann1 on 04 Dec 2010, 00:32, edited 1 time in total.
- ceeann1
- Posts: 106
- Joined: 17 Nov 2010, 20:00
- E-book readers owned: Several Palm PDA's
- Number of books owned: 700
- Location: Albuquerque, New Mexico
- Contact:
Re: Input on the best way to build a portable scanner
Moved to the Origami Scanner- a folding book scanner
In the next post spamsickle was kind enough to post a definition of Keystoning for me.
In the next post spamsickle was kind enough to post a definition of Keystoning for me.
Last edited by ceeann1 on 04 Dec 2010, 00:33, edited 3 times in total.
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Re: Input on the best way to build a portable scanner
"Keystoning" is when the image of a rectangular page appears as a trapezoid (like the "keystone" at the top of an arch). It's caused by perspective, when the "film plane" isn't parallel to the plane of the page.
- ceeann1
- Posts: 106
- Joined: 17 Nov 2010, 20:00
- E-book readers owned: Several Palm PDA's
- Number of books owned: 700
- Location: Albuquerque, New Mexico
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Re: Input on the best way to build a portable scanner
Reply to spamsicle: Ok that is what I thought keystoning ment. An optical distortion, in effect. I always intended to keep the plane of the cameral lens parallel to the plane of the book page. I appreciate the tip on how to do that!!!
I guess what I am left with is why would anyone go outside the the 90/45 degree parameters? What is there to gain?
I do have a modification to my previous camera mount design I will post asap that should take this into effect.
12-03-2010
the post of the camer mount will be in the, "Origami Scanner- a folding book scanner", thread.
I guess what I am left with is why would anyone go outside the the 90/45 degree parameters? What is there to gain?
I do have a modification to my previous camera mount design I will post asap that should take this into effect.
12-03-2010
the post of the camer mount will be in the, "Origami Scanner- a folding book scanner", thread.