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Old 13-04-2012, 03:00 PM
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GC - South Aus
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RE: Focal Ratio

G'day Paul

Quote:
Originally Posted by Matt Starwave View Post
Quite creative some telescope makers. Half a bino by the looks of it for a finder. Must be a f9 or larger comparing height to other objects around it. Another interesting project to follow. Great mount too, looks heavy alright.
Yes it is quite creative and the bino focuses really well too, but probably won't be staying on in the long run.

In relation to the f/ratio the OTA has 3 sets of 4 holes all in the exact same location (ie in line) and size but at different distances (up and down) on the OTA so I feel that the tube f/ratio can be altered.

At the mirrors present location, if my calculations are correct it comes in around f8.8, so yes f9, but like I said it probably can be made faster.

Regards & Clear Skies

Gav
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