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leinad
11-09-2013, 01:45 AM
Could someone please confirm for me the backfocus lengths are as below and I haven't lost my mind(though I have lost my notes). :screwy:
This accounts for the CAA Rotator. I'm going through the process of sourcing adapters and need to make sure I get the right lengths, accounting for the ccd back focal plane/adapter and focuser to be racked out half way at 15mm, for even in/out autofocus travel.

Therefore backfocus from CAA is:

F/5 @ 153 mm
F/3.6 @ 47.2mm

Thanks

alocky
11-09-2013, 11:15 AM
Daniel - sorry I thought you'd sorted this out. I will measure mine up as soon as I get home tonight. You've got the CAA rather than the captain's wheel, right?
Cheers,
Andrew.

leinad
11-09-2013, 12:49 PM
No prob :)

Yes thats right. CAA takes up 25mm.

gregbradley
12-09-2013, 07:55 PM
Anacortes has a section with all the Tak backfocus distances etc.

Greg.

leinad
12-09-2013, 08:12 PM
Thanks, I think I've managed to solve them. confusion with the FR back focus was measurement from the FR not the start of the focuser tube. This doesn't seem to be specified anywhere. and then this confused with focuser travel needed.