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Charlie in Dayton
2005-Jul-20, 04:26 AM
...oooooooogh...sooooooooo many things all boiling at once...

The Englishsters [/obscure Andy Griffith Show 'Ernest T. BassŪ' humor reference] make a nice little thingamabobberoo that holds a Meade DSI camera and 35mm camera lens (work with me, this will make sense). The carrier has a 1/4" Whitworth thread, supposedly to allow tripod mounting. Now we all know that Whitworth threads are the sole reason for the British auto industry's mystique...anyone know if a BSW (British Standard Whitworth) 1/4" thread is the same as our 1/4-20 tripod thread? Several conversion charts tell me this oughtta be so...

They don't sell these little beasties over here that I've seen...they let you put your 35mm camera lenses (various mount formats) on a Meade DSI and use it that way...I think I've even found an adapter that lets you use Pentax K mount lenses on this...if that mythical uncle of mine ever kicks off and leaves me those two East Texas oil wells, that would be the time to get into computerized astrophotography (don't own a laptop yet), and this little adapter setup would be ideal for certain astrophoto situations. Imagine the pictures you could take with a Meade DSI with a 50mm or 28mm wide angle lens on it mounted on a tracking mount of some sort...15-20 minutes of frame grabbing and some Registax'ing...what pictures you could get!!! ...hmmm...wonder what they'd give me in trade for a couple of close yet otherwise worthless relatives...

I've been a devotee of binocular astronomy for awhile now, and are firmly convinced of the advantages of the simple monopod for viewing. I have a mount that screws on the end of a standard utility stick (the mount is a modified paint roller), and the bino L-mount screws onto that...but the 'paint roller' has this huge platform-like surface that's awful big and bulky...what I'd like to get my grubby little paws on is a camera ball-and-socket mount-type-thingie that's 1/4-20 on one end to go into the bino L-mount, and can just stick on the end of something to use as a monopod...maybe have the threading to match the industry-standard threads on broom handles or paint roller extension sticks...it would be the equivalent of a photo tripod head, just more compact. Loosen the thumbscrew to let the ball move around, tighten it just a tad for a friction drag...yet the whole thing just kinda screws on the end of a hardware store broom handle or the like...anyone heard of anything vaguely similar to this? Anyone got any ideas on how I might be able to whomp up something like this on my own? Broom handle with 3/8" bolt screwed in the end and cut off mayber 1/2" long, and screw a good sturdy camera ball-and-socket mount onto that?

I'm open to ideas on any and all of this...

frogesque
2005-Jul-20, 09:43 AM
I/4 x 20 BSW will fit a 1/4-20 NC thread but the fit is not good. BSW profile is a 55 deg. thread form whilst NC is 60 deg. so you don't get proper flank mating. It would be OK for occasional use with light loading. To protect any expensive kit (which is usually soft die cast or alluminium, rarely brass) I would use a hard nylon screw so if there is any thread damage it will be the screw that suffers.

Some model suppliers and tool purveyers do still stock 1/4 BSW taps and dies. If you are really desperate I could probably track them down over here for you.