Kevin Francis

Here's a youtube video on the subject that could save you $$$ in the future.

Here's another method to achieve prime focus.  Video included.  Author will also support your installation.

Here is a DIY source

https://kevinrfrancis.com/2020/05/polar-alignment-camera-install-polar-scope/

Shown are two of my photos of M31.  Two very different outcomes from two nights of imaging.  Main difference to me was the number of light on around my neighborhood at the time.  Maybe your experience can shed additional light on why the difference (yes the ISOs are very different). 

Equipment used for both photos:

Telescope & Mount: Orion ST-80 with Astroview Mount with RA motor

Camera: Canon EOS XTi

Guiding: None

Location: Carrollton, VA

Sky: Bortle Class 5

Acquisition details of photo on left.

Acquisition & Calibration:

\- Filter: None

\- APT (Astrophotography Tool)

\- ISO 1600

\- 40 Light Frames @ 120 s

\- 62 Dark Frames @ 120 s

\- 19 Flat Frames

\- 60 Bias Frames

\- Total Integration Time: 80 minutes

Acquisition details of photo on right.

Acquisition & Calibration:

\- Filter: None

\- APT (Astrophotography Tool)

\- ISO 800

\- 14 Light Frames @ 180 s

\- 30 Dark Frames @ 180 s

\- 50 Flat Frames

\- 60 Bias Frames

\- Total Integration Time: 80 minutes

Additional details can be found on my blog.

I have a design in my head to improve the stability of my setup with piping, a few 3D printed joints and bearings, and 3D printed brackets for the mounts.  I'm curious if anyone has attempted anything like this before.  Would like to see your results.

Very nice work! I was going to comment about the need to reduce noise in your photo, but seems you have that advice already.  I see that you used GIMP to post process.  Great choice.  Here's a good video on how to process using GIMP.   Good Luck and great start.

Purchased the Orion Astroview 6 three years ago.  Found out later that I could not attach my Canon EOS XTi and obtain focus.  Everything I saw online required sawing and drilling the OTA.  That makes the scope a single purpose telescope.  After reviewing the primary mirror holder I created a holder that moved the mirror 25 mm.  This way I can keep the scope ready for visual observing and sell later if I desire.  If you're interested in saving a few dollars in this hobby check out the link below.

How I Moved Prime Focus: Link to the detail.

Photo from this telescope