PDA

View Full Version here: : DIY 0.75 Focal reducer & T to C adaptor


Karls48
23-07-2006, 12:20 PM
Hi all
If you purchased scope from Andrews, you probably got free 32x10 binoculars with your scope. Binoculars most likely don’t get much use because – well they are for free. But you can put it to good use. With few other bits and pieces you can make 0.75 focal reducer, T to C adapter and 10 x 32 finder scope.
You will need Camera adaptor tube type from Andrews - $25 and 5 mm C Mount Spacer Ring, from Altronics - $5. You will also need - Araldite and piece of brass or copper shim.
Remove rubber cover from the binocular with fixed ocular. That will give you access to the screws to disassemble it. Keep the other part with adjustable ocular for finder scope. Remove front lens doublet. Unscrew the nosepiece from the camera adapter.
Binocular lens is just a bit smaller then inside diameter of the nosepiece. Blacken the edge of the lens, pack it up with the shim and glue it to nosepiece. And you got 0.75 Focal reducer. It will also give you right way up image without need for diagonals.
Tested with Celestron 102 x 500 and 80 x 400 refractors.
T to C adaptor.
I needed adaptor 22mm long. Made one form left over Camera tube. Cut off the end with female T tread. I cut it 24mm and then square it up on belt sander. Again the C mount space ring is bit smaller then the inside diameter of Camera tube. Pack it up with the shim, hold it in place with camera canister and glue it.
Karl