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p1taylor
15-07-2010, 11:04 PM
Hi Have just received my STOAG9T2, but no info on haw to setup, imaging camera will be SX h9c, guide camera SX lodestar plus t2 to c adapter, to get so I can rotate h9c it needs 10mm between camera and oag, will it need same spacer to lodestar to get focus on both, or do I not need any spacers at all, hope this makes sens.

peter

marki
16-07-2010, 01:15 AM
Hi Peter

The main thing is that the distance from both chips are exactly equal so both come to focus at the same point. Basically you need to setup the OAG so it fits then measure the distance from the face of the prism to the face of your imaging chip (find out the backfocus for your camera). This is the distance you must set your guide camera chip to. I have to add about 60mm of T2 extensions to the guide cam side to get close ( QHY9 + FW + QHY5). I then use the thumbscrew on the side of the prism stalk to get the exact focal point. Be careful when rotating the camera (hang on to it) as the three tags that lock the lot together have limited purchase and will come free as soon as you back off the thumbscrews which hold the main body to the adaptor.

Good luck :thumbsup:

Mark

p1taylor
16-07-2010, 01:45 AM
Hi Mark

Distance of imaging camera is 36mm made up of 19mm from prism, 17mm from face of h9c to chip, sorry but how do I find back focus of camera, from top of prism stalk to prism is 38mm, face of lodestar to chip is 12mm, I think I have missed something as your guider seames way up, the extra 10mm on camera side lets me rotate 360 degrees on a dovetail.

peter

p1taylor
16-07-2010, 07:52 AM
Hi Mark,

I think I just twigged what you meant distance from prism to camera and prism to lodestar to be same so I need 14mm in camera so thy are both 50mm, thanks for info.

peter

marki
16-07-2010, 11:29 AM
Yep, get it in the ballpark then fine adjust by moving the prism stalk up and down.



Mark

p1taylor
16-07-2010, 10:51 PM
Hi Mark
Will try that when we get clear night, will let you know how I get on.

peter