Advice on Coma Corrector and reducer - Forums

Topic starter

May 7, 2023

Hey

I have a Skywatcher 200DPS f/5 8” newtonian and are looking to add a Coma corrector to my setup.

I have the default focuser that came with the Telescope and currently imaging with an EOS 50D - which will soon be replaced with an ASI2600.

Any suggestions on which CC to invest in?
Is it worth it to use a combined CC/Reducer?

Engaging

Tim Ray

May 7, 2023

I have had good luck with my Baader Planetarium CC. Lots of nice images on AB with the Quattro CC from Skywatcher…

CS - Tim

Oscar H.

May 7, 2023 · Edited: May 8, 2023

According to a lot of people; the absolute best you can get is the Starizona Nexus. You can buy ithere

I know people will say "the best is the TeleVue Paracorr" but I think otherwise, since there are much moresatisfiedpeople with the Nexus.

Another good option if you're a little low on money is the "Badder MPCC" ☚

And yet another CC from Sharpstar which has a .95x reducing feature and less spherical aberration than the Baader CC (so says the Astrobin community if I remember right).
You can purchase it here.

All these will work best with up to an APS-C format.

Of course, another option is the cheap GSO CC, but I wouldn't buy that unless I will use eyepieces also.

Jamie Macdougall

May 8, 2023

Also interested in this exact question, though I don’t want any reduction in focal length. so that would point me toward the Baader MPCC.

However, I’m currently using the standard skywatcher coma corrector/reducer which seems to do the job fine, and is practically the same cost. I’m not sure it’s worth buying the MPCC just to get rid of the reduction - is there any improvement in image quality?

Mike Dobres

May 8, 2023

I have been using Skywatcher F5 coma corrector on my Skywatcher 130 PDS and my 14" GOTO Dobson Newtonian tubes for several years (it came with the the Dobson when I bought it used

.

http://skywatcher.com/product/f5-coma-corrector-2/

FYI - spacing from the coma corrector to camera lens is fairly critical.. See this discussion:
https://www.astrobin.com/forum/c/astrophotography/equipment/coma-corrector-backfocus/

Mke

Christian Bennich

Topic starter

May 8, 2023

I chose to go with the TS-Optics GPU CC and look forward to testing it.

Well Written Respectful

Kevin Dixon

IOTD Staff

May 8, 2023

I highly recommend the Starizona Nexus 0.75x focal reducer/coma corrector. I have gotten excellent results with the Nexus and my Skywatcher 8-inch Newtonian.

Clear skies,
Kevin

Well Written

Brian Puhl

IOTD Staff

May 8, 2023

I started with a Paracorr. Don't get me wrong, I absolutely love it… But it's not made for my F/4 scope. The focal plane is a bit different and I have to put a spacer on the coma corrector in the focus tube to achieve focus. This also has been causing some pinched optics that are tough to alleviate. There's no way to screw them in like on a refractor. Now I only recommend the paracorr if you have an ONTC with a moveable primary.

I picked up a starizona nexus awhile back and I can't say enough great things about it. For my F/4 scope, it brings me down to F/3 allowing me to suck in an incredible amount of light in a short amount of time. Downside is you'll need fast filters for it. Also, the vignette on APS-C is pretty strong but still easily correctable.

Both of these correctors are highly regarded as the best, and I would definitely agree. The paracorr just isn't as flexible in my setup. It might work on your F/5 scope, but it will slow it down a tad. Having both also makes for a rather flexible system, even though I have issues with the paracorr. (you can see the problem in my recent images if you look at the stars).

Feel free to browse my recent gallery tho, lots of paracorr and nexus stuff in the past month or two.

Helpful Insightful Respectful Engaging

Dale Penkala

May 8, 2023 · Edited: May 8, 2023

My personal experience is the Sky Watcher Coma Corrector is excellent. You can see many examples on my profile here: https://www.astrobin.com/users/DalePenkala/
Prior to that I used my paracorr but as its been mentioned above it pushes the focal point out much further then I would prefer not to mention it does add 11% magnification to your fl.

The Starzona unit many have great things to say about it and do not doubt it one bit. I just have no experience with it and honestly I don’t want to deal with vineting anymore then what I am now so I just stay away from it and I prefer to keep my native fl of my 12” f5. Again many use it and have great results with it.

Dale

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