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Subject: LarScan works!
From: gbraun@mail04.mitre.org (Gary A. Braun)

I've been working on my LarScan on and off for about 4 months, and just finished it the other day. I shot two rolls of Ektachrome and was astounded that it actually worked (since nothing I makes ever works the first time!)  I'm still getting a bit of minor banding which I attribute to a slightly off-center drive pulley, and I need to recalibrate the "infinity" mark on my lens for sharper images (even though they are very good now).  Otherwise, I'm extremely pleased with the performance.

I used an old Zeiss folding camera for the body, an Olympus 24mm lens which I already owned, and various bits and pieces (DC gearhead motor, bearings, miniature nuts & bolts, etc) from electronic surplus stores and RC model shops.  An excellent source for DC gearhead motors is:

C & H Sales Company
P.O. Box 5356
Pasadena, CA  91107
Telephone 818-796-2628

My next project is to build a pan camera with a surplus 3" Zeiss Planar aerial camera lens.  Hopefully this one won't take as long!
Cheers,
Gary

Hi Bob,
I thought I'd let you know I think I've finally got a fully functional LarScan!! I found the (best) zoom lens setting and expoxied the barrel in place along  with the focus ring so it can not move.  Solved the banding problem related to the take-up spool! I made a  spring out of a piece of 1/32" stainless cut about 3/4" wide and about  3.5" long. Bent it to an elongated "S" shape and drilled a hole in it.
This was attached to an adapter that fits the "hot shoe" mount on the  top of the camera that has a 1/4-20 bolt sticking out the top with a nut and washer to hold it down. With this arraingement I can adjust  the pressure on the spring simply by tightening the nut.
   
In the future I'd strongly suggest you not deal with fixed focal length lens's. By my observation the size of the disk is critical to match the focal length. When I do the math based on my settings achieved, the disk size is 69.2mm which gives me a focal length of  34.6mm. Nikon claim an accuracy of +/- 1% and my lens must be to the plus side. Their was no way to make the fixed lens work with that disk. A difference of .4mm doesn't sound like much but it must have been enough to keep it from working.
   
I also got the bearing freed up faily well, I hooked up my Dremel tool  with a rubber band and spun the hell out it for about 15 minutes.  If you're interested, as soon as I get some images that I'm willing to  have "published" I'll send you a few if you should care to use them on  the web site for your advertizing purposes. Let me know.   

Thanks,
Mike Rote