Bought the wrong combo? Atik camera + SX OAG / FW

[HenryNZ]

I have recently purchased a second hand SX FW+OAG to go with my Atik 460ex camera, it is still in the mail but alas I think I might have made the wrong purchase!!

I already have an Atik FW and OAG but the Camera+OAG+FW back focus requirement is in the order of 61mm (13 mm camera+22 mm FW +24mm OAG +2 mm for the adaptor to the focal reducer) which is way out of spec for two of my reducers.

So I thought since SX OAG + FW including the adaptors have a back focus of 42 mm, this would be perfect for my Atik camera (total 55 mm).

But then I started reading about how the OAG may not be able to reach focus if I simply go camera>FW>OAG>reducer because the OAG is designed expecting the main camera to have a back focus of 17 mm. In other word, with my Atik camera, the guide cam will not reach focus (the focal plane is still inside the stalk). To make it work I have been told I may need spacer to increase the back focus of my Atik to 17 mm'sih, but then this negates this whole exercise of buying the SX as I am literally back to square one!

 

Someone please tell me this isn't true...

 

I am just hoping that the guide cam focuser of the OAG can be adjusted enough to still allow it to focus when using my Atik camera. My guide cam is a original Lodestar BTW.

 

 

 

Edited March 20, 2017 by HenryNZ

[Davey-T]

Shouldn't it go camera / filter wheel / OAG ?

Dave

[HenryNZ]

Yes, you are right. It should be camera>FW>OAG. I have corrected my first post. 

Question is still the same though...

 

Edited March 20, 2017 by HenryNZ

[Gina]

When I was using an OAG I had to shorten the stalk to get focus.