Celestron EDGEHD 8" connection with OAG-L and ASI 533MC PRO Camera

TomRad

Hi All

I have an issue how to properly connect my equipment and achieve 105 mm backfocus distance which is required for Celestron EDGE HD 8'' with REDUCER LENS .7X - EDGEHD 800 (https://s3.amazonaws.com/celestron-site-support-files/support_files/94242_reducer_inst_sheet.pdf).

Recently I purchased new OAG-L and want to install it properly with my scope.

My current equipment:
1/ Celestron EDGE HD 8'' (https://www.celestron.com/products/edgehd-8-optical-tube-assembly-cg-5-dovetail#specifications)
2/ REDUCER LENS .7X - EDGEHD 800 (https://www.celestron.com/products/reducer-lens-7x-edgehd-800)
3/ OAG-L (https://www.zwoastro.com/product/oag-l-oag-l-68/)
4/ ASI 533MC PRO Camera (https://www.zwoastro.com/product/asi533-pro-series/) + attached standard adapters
5/ ASI 220MM Mini (mono) (https://www.zwoastro.com/product/zwo-asi220mm-minimono/) for guiding.

Regarding backfocus, my understanding is that 105mm distance is calculated from REDUCER LENS .7X - EDGEHD 800 to ASI 533MC PRO Camera Focal Plane (https://s3.amazonaws.com/celestron-site-support-files/support_files/94242_reducer_inst_sheet.pdf).

I know I need also T-Adapter from Celestron. I have this one: Celestron T-Adapter for 8" EdgeHD Telescopes # 93644 (https://agenaastro.com/celestron-t-adapter-8-edgehd-telescope-93644.html). I am afraid however this element is too long. Assuming 105mm max length minus 55mm ZWO settings I need to find T-Adapter of 50mm.

Questions:
(A) Can you please help me to fix a proper distance between these elements assuming I want to install OAG-L in the middle?
(B) If I need additional adapters, what exactly do I need to buy?
(C) Should I keep the same distance (length) between RDUCER and ASI 533MC PRO Camera, as well as between REDUCER and ASI 220MM Mini Camera?

Thanks for support!

Tomasz

Tech@ZWO

TomRad
1 You can refer to this connection way to get 55mm back focus.

The connect only the long extension of this adapter to get 105mm back focus.
https://agenaastro.com/celestron-t-adapter-8-edgehd-telescope-93644.html

2 Only need the adapter to get 55mm back focus on the pic of the 1 point.

3 Yes, need to make sure the distance from the OAG-L prism to the guide camera sensor is the same as the distance from the OAG-L prism to the main camera sensor.