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Thursday, October 21, 2010

Matching a web camera with a standard camera lens - some assembly required: August 2010

Matching a web camera with a standard camera lens

Thursday, August 26, 2010

Webcam Details

Matching a web camera with a standard camera lens turned out to be an interesting task, there were several different methods i have seen but it wouldn't be very fun if i didn't do my own

I started out with a cheap pvc conduit box and built a mounting system that could be adjusted in all directions, i drilled out holes and epoxied  bolts down so that i could thread bolts in each corner. then thread locked bolts on each end and epoxied rare earth magnets. The idea was to hold a sheet of steel or plastic while allowing freedom to center the sensor. Regular epoxy did not hold very well to either the bolts or the pvc so i used jb weld. It worked out quite well since i need a fair bit of control over the amount of magnification. To prevent light reflecting on the inside i spray painted the entire thing flat black

I decided to go with a standard m42 lens, they use a standard threaded mount and it is easy to pick up a suitable lens for a decent price. I picked up a cheap adapter that allows a m42 lens to be used with a different camera mount, filed down the bayonet tips on the back and used it for a flange to mount the lens . I made the mistake of not having enough distance between the lens and had to use extension tubes to increase the distance.

For the lens i picked up a Helios 44-2 for 30 dollars including shipping, with a focal distance of 58mm and a manual aperture of f16 down to f2.8.

I went with a logitech c600 webcam, it was the best fixed focus one i could get. At 1600*1200 video resolution at ~15 frames per second im not complaining. After gutting the camera and removing the lens i simply mounted it on a square of thick plastic with some hot glue, it is held on by rare earth magnets on either side. For my first test subjects i used my large collection of eproms, my first tests allowed me to see the NEC logo and manufacturer's code on an old 8051 micro controller. Quartz windows do unfortunately give a bit of distortion, also the depth of field is very narrow. I'm building a cross slide to properly hold and focus with this thing. So far i have been focusing manually by sliding it back and forth until the target comes into focus and gently nudge the camera the rest of the way.

Wednesday, August 25, 2010

Modified Webcam

I just finished my webcam i am using for a telecine project

Im not entirely sure what the magnification im getting with it but it takes some very excellent pictures:

Go there...

Cool!:) I have an old JVC Pro Video Camera Lens that I was thinking about trying to fit to my Web Cam, just to see if I could get a better Picture, with Zoom and Better Focus. I held them together, but I could see more of the inside of Lens than what was out in front of it. So, I figured it was a lost cause. The mount on the Web Cam has broken off and it's a little round jobby. So, I got to thinking and looking around my garage and there it was! A perfect new mount for my Cam! An old 1 and a half inch PVC Female Y::) I Silicon-ed the Cam in one end and drilled a 1/4in hole in the bottom of the other and now I can mount it on my mini Tripod. Also, I can set my other Web Cam in the other side of the Y if desired and run them both at once. I need to make a way to secure the second Cam though. Now I'm thinking... if I can find or make a Reducer to fit the threads on the Lens. Then they may just match up and work together. I will follow your lead and blacken the inside of the PVC (its white) or just get another Y or Collar. One that is black. I think I will need to figure out how to make those darn LCD lights in the Cam stay off too. I hate having those things shinning in my face anyway. I run Fedora 13 and Debian now and the lights stay on all the time. They are only suppose to come on when it gets too dark in the room. That feature did work in WinXP (I hate to admit;) Thanks for posting your great Projects!:)



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