Coma Corrector Recommendations.

[ribuck]

Hi All,

I'm looking into buying a coma corrector for my Skywatcher 200P F5 newtonian.

I'm planning to mainly use the corrector for imaging with my QHY9 + 2" filterwheel, but i would also like to have the possability of using it visually with my 1.25" Baader hyperion Zoom.

I would like people's views on the best all round coma corrector, that is easy to use with my ccd and single 1.25" Zoom eyepiece.

If anyone has anyone of the following correctors that they currently use, i would be keen to hear your thoughts on them (setting up, performance, results etc)

looking at the following possible option :

Baader MPCC Photo/Visual edition

(Have heard there may be some issues with Skywatchers)

Televue Paracorr

(Excellent reputation, but not sure about increase in F/L and costs more)

New Skywatcher Corrector

(Not much information available on this, Some mixed reviews but a great price and optimized for my scope @ F5, however all websites seems to mention using it with DSLR, but not CCD)

[Deneb]

Im currently using the Skywatcher, but mind you im only imaging through DSLR, I think FLO is looking into what distance it offers when using CCD, as I said in my review maybe the Baader is more suited for CCD work.

Cheers

Nadeem.

[ribuck]

Hi Nadeem,

I like the idea that the skywatcher coma correct is optimized for my skywatcher scope. I'm just waiting a week or 2 to find out what distance is required from the surface of my ccd chip.

[albedo0.39]

Hmmmm.... I've come to know a whole heap of people with scopes much faster than F5 and they insist on not using Coma Correctors for various reasons. However, drop below F4 and you will start needing one. At F3.7 you are right in the zone.

So, how do they all escape this obvious upgrade ? Well, they all seem to have Pentax, Takahashi, Zeiss or Televue EP lenses which seem to have the edge corrected so much better than other (chepaer) lenses. I've triaed all this expensive stuff in my F4.5 and it a whole order better than I imagined - especially from a dark site.

If you have not enough £ for this kind of exotica, why not consider the excellent William Optics UWAN 's or for a touch less £, the Skywatcher Nirvana EP's. Both are excellent and will work in your F5 with minimal coma.

Of course, when you are hunting DSO's at medium to high power, you are perhaps looking at a narrower FOV so the edge coma is not so bad.

But... that's just my opinion (which of course, you can ignore !)

Cheers

[athlon]

I use a Baader MPCC with a QHY8, and have used it in the past with a Canon 1000D, also on a Skywatcher 200mm F5 newt, it does move the focus somewhat, but with the adaptor attached to the MPCC i can get it to focus, provides great results.

[ribuck]

albedo0.39,

I'm looking to do prodominantly photograpic work, so a coma correcotr is definately needed.

Athlon,

That's good news about the MPCC. I alway get confused about the in and out focus. When you say the baader pushes the focus out, does that mean i need the more back focus or inward focus.

When i say back focus i mean the draw tube coming futher out of the scope, and further into the scope for inward focus. Which one is it that newtonians normally lack ? in or out ?

Rich.

[themos]

In

[ribuck]

So with the the baader, do i need more inward focus travel or willit push out so that i gain more inward travel on the focuser tube ?

[ribuck]

Does anyone else have any views on the comparisons of these correctors ?

[athlon]

So with the the baader, do i need more inward focus travel or willit push out so that i gain more inward travel on the focuser tube ?

with the MPCC attached, you dont have to wrack the focuser out as far as you would, i usually find that putting the camera right in to the top of the focuser wont work, and its a balancing act of getting the adaptor kinda part way in, and the focuser partway out, to achieve focus

but it does work