Lasers, eyepiece holder offsets, and tilt (collimation issues)

[BeardFace (Nial)]

Hey all,

Just wanted to get people's thoughts on the following problem. I have a howie glatter laser, and when I push it into the back of my RC12 (and rotate it to ensure there's no tilt from the laser) I can set the tilt adjustment screws to get the following result:



Which is good, however when I clamp the eyepiece holder, it pushes the laser up like so:



Which certainly isn't ideal. Putting the laser further back in the imaging train shows the same offset result.

So my question is, how do you fix something like this? Should I be adjusting the tilt on the scope to accommodate for issues caused by the clamp, or do I need to find a way to fix the offset either through getting a better clamp or a tilt plate, or other something else? I'm using a secondary mirror focuser, and a fixed focus camera adapter from Rainbow Astro. However the adapter only has two grub screws for the eyepiece holder, and no ring.

Any help would be greatly appreciated!

[gts055 (Mark)]

Hii Nial, I am not into imaging but when collimating I sometimes wrap turns of cellotape around loose fitting items to get better centering. Mark

[BeardFace (Nial)]

Yeah, I've been considering the same. At least to keep t adapter centred until the grub screws secure it

[doug mc]

There is a gap between eyepiece holders and whatever you put in them. Sometimes too much. A self centring eyepiece holder may improve things. gts055 has a working solution.

[PRejto (Peter)]

This should do the trick:

https://www.testar.com.au/collections/baader-clicklock

[BeardFace (Nial)]

Originally Posted by PRejto

This should do the trick:

https://www.testar.com.au/collections/baader-clicklock

Yeah, I was hoping to use a click lock, but I don't think any would work with my fixed focus adapter:

[Joshua Bunn (Joshua)]

Threaded connections are the only way to go. I threaded my laser collimator, then made up an adapter to thread the laser to the focuser. Its very secure and repeatable.