1.25" Coma Corrector for f5 Newton

[NorthernLight]

Hi guys,

I love my 6" f/5 Newton, it has a lot of really good qualities.

BUT it comes with a 1.25" focuser and I cannot find a Coma Corrector in that dimension. A 2" coma corrector can be had everywhere but I do not want to change my focuser just to buy a coma corrector.

Has anybody got a 1.25" coma corrector to sell or know where to get one from?

Cheers,

[Karlzburg]

I thought that scope came with a 2 inch focused and has a 1.25 inch reducer?

[raymo]

That is correct Karl.
raymo

[ChrisV]

So if 2" there's a baader mpcc on sale in the classifieds!

[NorthernLight]

Hi guys,

my scope definitely has a 1.25“ focuser. It’s the Celestron scope in my signature.

Cheers,

[raymo]

I'm confused, there are two different Omni XLT 150s, a 150mm Newtonian
reflector which changed from a 1.25" focuser to a 2" in 2013, and a
150mm refractor which has a 2" focuser, but I think this scope was discontinued a while ago. What exactly do you have? If you have a pre 2013 Newt you can fit it with a 2" focuser.
raymo

[billdan]

Not sure if you are into DIY or not, but this guy made his own 1.25" coma corrector with off the shelf lenses, cost him $50 for the three lenses.


https://www.cloudynights.com/topic/474128-3d-printed-coma-corrector/

[NorthernLight]

Thanks for that link. I wish I would be able to do that. But I am not that talented. In the end I may have to consider replacing the focuser.

[NorthernLight]

Hi Raymo,

My scope is from 2008 and came with a 1.25“ focuser. I haven’t used this scope in a long while but would like to take some photos with it. My hope was that there is a commercial market for 1.25” coma correctors just hidden from my view. But if changing the focuser is the only way, then I might have to consider that and do some research.
Thanks anyways!

Cheers

[raymo]

Before going any further I would suggest that you ensure that your Newt
can be used for imaging. Many Newts are made for visual, and a camera cannot get close enough to the scope to come to focus. If this is the case
the primary mirror would need moving further up inside the tube.
raymo

[NorthernLight]

Hi Raymo, I have been imagining with it for quite some time but since I changed to the ED 80 I got allergic to the coma :)

[billdan]

Hi Max,

This will give you some ideas on how to make the focuser hole larger.

https://www.cloudynights.com/topic/619137-best-way-to-enlarge-focuser-hole-on-starblast-6-ota/

Cheers
Bill

[NorthernLight]

Thanks Bill. Really helpful article. I guess I’ll have to start thinking about another focuser and what type of coma corrector I want. But I’m in no rush and think these are questions for another post at the time that budget and time allow a bigger investment. Thanks for all your helpful posts. Too bad though that there doesn’t seem to be an easy fix i.e. a commercially available 1.25” CC for a good price.

Clear Skies!

[billdan]

While I was browsing Cloudy Nights this morning, it appears that Televue made a 1.25" Paracorr in the past. So you may be able to find a second hand one in the various Astromarts around the world.

[NorthernLight]

Hi Bill, great!!! I’ll start hunting for one:thanx: