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Using the ST8300M with the SX FW + SX OAG

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#1 saadabbasi



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Posted 30 January 2013 - 04:36 PM

Hello all,

I'm wondering weather anyone here has used the above mentioned combination? I am not sure if I will achieve focus on both cameras with this setup - though I have used a OAG before, it has been a while since I did some astrophotography and I am a bit rusty.

My guider is an SX Lodestar which has a back focus of 13mm - the Lodestar has a C-Mount thread which screws directly on top of the OAG. The ST8300M has a back focus of 17mm, and the FW has about 25mm of back focus. This brings the prism to main camera distance to 17+25 = 42mm.

The SX OAG does not list the prism to guider length so I'm not sure how to calculate this bit.

#2 DeanS



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Posted 30 January 2013 - 04:51 PM

I use it with my ML8300 and it works. Depending on how you connect them together it could change the spacing a bit.

The ML8300 has 25mm chip distance with the 2" SCT adapter so I had to add a 5mm extension to my lodestar and now it reaches focus fine. So if you can connect directly to the camera you may not have to do anything. Really only way to tell is try it out.


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