31 replies to this topic

[joshman]

I use the Hotech 2" SCA flattener with my 102ED scope. You can remove the self-centering contraption off the back and thread it directly to your drawtube. From memory its a standard 48mm thread. I found the SCA wasn't rigid enough in my drawtube and the sensor tilt changed all over the sky.

[slackline]

My drawtube just has the eyepiece clamp.  Does that come off?  I don't have any documentation on the scope.  I bought it from Orion as a blem.  It has a spot where the paint was repaired on the body of the scope.

[rlmxracer]

My drawtube just has the eyepiece clamp.  Does that come off?  I don't have any documentation on the scope.  I bought it from Orion as a blem.  It has a spot where the paint was repaired on the body of the scope.

Most are threaded onto the draw tube just make sure to check for set screws that some have to secure it on.

[slackline]

No set screws that hold it on or lock it on.  The eyepiece clamp screw and a set screw 180 degrees from the clamp screw are all that are there.  The set screw is just in there to block light or fill the hole.  It does not do anything.  I took them both out and twisted pretty hard with no movement.  I'll just wait for my adapter I guess...

[BetaOrionis4]

Update. Flattener eventually arrived and I put everything together and got it to work:
 

- After the focuser I have the two M63 extension pieces that came with the OTA. 
- Then comes the flattener, a 16,5 mm distance piece (M42) that came with the ASI 2600 MM, the filter wheel (adding 20 mm), another 2 mm distance piece and finally the camera (17.5 mm from front to sensor). 

 

This gives a "backfocus" of 56 mm (16.5 + 20 + 2 + 17.5). Given I will use 2 mm thick filters, the backfocus should ideally be 55,7 m, so pretty close and maybe close enough.
 

One challenge I had to solve was the significant added weight on the back. The dovetail piece of the original OTA was too short to be able to achieve balance. So I bought a 33 cm long Sky Watcher dovetail piece. This needed, however a bit of metal work (drilling, threading) to fit to the handle of the OTA.

Now everything is fine and the other night I could test everything. Feels I am ready to go once I have better cabling and final solution for the power supply (got a 10 A Pegasus power supply that broke after 30 minutes of use. Warranty case so new one will arrive next week and I hope it will last longer).

 

Album: ED102 Setup

6 images

0 comments

[joshman]

So, I notice that you're using the V2 of the EFW, that means your can remove the black tilt plate on the front of the camera, and connect the Filter wheel directly to the camera body. It's a lot more rigid and secure. You will need to find 7mm of spacer to make up the 5mm of the tilt plate, and 2mm of the threaded joiner.

 

You will also need to put some tape or something over the screws holes on the filter wheel, otherwise you'll have light leaks galore!

Edited by joshman, 16 March 2025 - 03:07 PM.

[BetaOrionis4]

Thanks for the suggestions!

 

 

So, I notice that you're using the V2 of the EFW, that means your can remove the black tilt plate on the front of the camera, and connect the Filter wheel directly to the camera body. It's a lot more rigid and secure. You will need to find 7mm of spacer to make up the 5mm of the tilt plate, and 2mm of the threaded joiner.

 

You will also need to put some tape or something over the screws holes on the filter wheel, otherwise you'll have light leaks galore!