2" screw adapter for 130PDS/MPCC and Laser Collimation

[starwatcher_ch]

Hello there

I upgraded my 130PDS recently with a 2" adapter with compression ring. Now I ordered a 2" screw adapter (https://www.teleskop-express.de/shop/product_info.php/language/en/info/p5417).

It seems to be great to avoid tilting and to create a rock solid connection between all parts, but I can't use my laser collimator anymore with this adapter! At the moment, I see 2 solutions:

1. replacing the 2" screw adapter with the original adapter/compression ring adapter for each laser collimation

2. collimate on a star directly with the DSLR

To be honest, I don't like the first or the second solution.

 

Has anyone had this "problem" before? And how was it resolved?

CS

Karol

[Pitch Black Skies]

On 10/05/2022 at 17:23, starwatcher_ch said:

1. replacing the 2" screw adapter with the original adapter/compression ring adapter for each laser collimation

I'm not a fan of lasers anymore due to their inability to help with rotation of the secondary mirror. You could literally have your secondary twisted a whole 45° and with enough adjusting of the collimation screws still get the red dot in the centre of the primary.

But sorry, to answer your question I think you will need to replace the screw in adapter with the compression one for each collimation or maybe just go back to the compression ring.

A third thumbscrew tapped into the compression ring ensures a more concentric fit when tightening. Definitely something to do if you haven't already.

If keeping the screw on adapter, you could try screwing the whole imaging train off in one go and have the laser and compression ring etc pre-assembled and ready to be screwed on in one go.

[starwatcher_ch]

What do you recommend for collimation instead? I also own a Cheshire eyepiece. but of course I've the same situation with it as with the laser...

Anyway, a third thumbscrew for the compression ring adapter is a really good idea! I'll go that way!

Many thanks!

[Pitch Black Skies]

31 minutes ago, starwatcher_ch said:

What do you recommend for collimation instead?

I recommend a Cheshire sight tube/Concentre for collimating the secondary, and a collimation cap for the primary.

These are the ones I use;

https://www.firstlightoptics.com/other-collimation-tools/stellalyra-premium-cheshire-collimating-eyepiece.html

https://www.firstlightoptics.com/other-collimation-tools/rigel-aline-collimation-cap.html

[Pitch Black Skies]

Join the 130P-DS if you haven't already. There's a wealth of knowledge and experience there.

 

[starwatcher_ch]

1 hour ago, Pitch Black Skies said:

Join the 130P-DS if you haven't already. There's a wealth of knowledge and experience there.

 

After reading the first few pages I suspect all my questions are already answered there 🙂

Thanks!

[Ratlet]

12 hours ago, starwatcher_ch said:

After reading the first few pages I suspect all my questions are already answered there 🙂

Thanks!

Only about 7000 more pages to go lol.

[starwatcher_ch]

7 hours ago, Ratlet said:

Only about 7000 more pages to go lol.

I'm on page 32 out of 153... so not as bad as 7000 😉 

I still have one question unanswered... I'm curious if I can find the answer on the remaining 121 pages... 🤯

If not, I'll come back 🤓