I am looking to get started with EAA and astrophotography and have a few questions about equipment and setup. I have a Celestron 800 EdgeHD with a 0.7 focal reducer on a CGEM II mount. I am considering a ZWO ASI294MC-Pro as the main camera and a ZWO ASI 290MM-mini as the guide camera. Both of these would be connected to the focal reducer using the ZWO OAG. Software wise either the ZWO ASIAir or SharpCap. Post processing will be decided later.
My questions/confusions come from the required back focus for this setup. I have read on the forum that Celestron requires a 105mm back focus when using the focal reducer. I have also read that you can’t use the Celestron OAG for this as it is too large and extends past the required back focus. ZWO literature indicates a 55mm back focus. ZWO also offers diagrams of configurations to achieve this but I am unsure of what I am trying to reach: 105mm or 55mm?
Once the back focus is determined, what equipment will be required to achieve it? I know that some of the components are included with the cameras and OAG mentioned.
Any assistance would be greatly appreciated.
Thank you in advance.