How to get focus on TEC 140 APO

floreatfocuser · #1 04-07-2010, 01:11 PM

I need some advice on how to get focus using my 350d on my TEC 140APO.

Have not been able to use for a few years, but never managed to get it to focus properly.

Question I have is how do I work out what I need to connect my 350d to the scope. I have done the basic stuff with t rings adapters but it won't gain focus.

Any help for a NOOB for astrophotography would be appreciated.

Cheers

Andy

DavidU (Dave) · #2 04-07-2010, 01:23 PM

Andrew, do you have the diagonal in the focuser??

floreatfocuser · #3 05-07-2010, 10:17 PM

No I didn't. Should I have?

Andy

gregbradley · #4 05-07-2010, 10:38 PM

I have a TEC180FL. I use a FLI Proline 16803 and the TEC field flattener. Basically there is plenty of room for focus there for that setup.

I take it you are not able to rack the focuser out enough to get to focus rather than rack it in?

In which case you need an extension tube to place the camera further out. You wouldn't put a DSLR on a diagonal
usually as it would throw the balance of the scope off and open the door for flexure.

There are plenty of extension tubes on the market. I'd try scopestuff.com. or one of the vendors on Astromart for DSLR accessories.

You can also post this question on the TEC Yahoo Group there are plenty who use DSLRs with TEC140's there.

Beautiful scope you've got there by the way.

Greg.