Baader MPCC

[markarian]

I bought this from FLO a couple of weeks ago and just had the first chance to use it tonight. I am totally amazed! I expected it to do a reasonably good job but it far exceeded my expectations.

The coma on my Skywatcher 200P was quite significant and beginning to really bug me so I had to do something about it. Getting a coma corrector to fit into the single speed crayford that came with 200P was yet another challenge. Solution involved a friend's lathe and hacking the 2" eyepiece adapter (ask if you want more info). It works well though.

Attached are some before and after shots of the bottom right corner of two images - full frame Canon 350D. Don't have a before and after of the same image yet, but I think the message is clear.

Mark

[steppenwolf]

This is an amazingly effective device isn't it! I use one on my SW 200 and 250 'scopes and agree that it is really effective. You are right about the lengths you have to go to to install it on these particular telescopes - I have the older R & P focus mechanisms and had to design a custom adapter to get all the spacing right and yet still achieve focus with my CCD cameras.

[Shibby]

Don't tempt me! I've only just started imaging at prime focus; I imagine I'll be wanting one of these soon... Already spent enough money recently!

[Digz]

Well the results speak for themselves really. I have one of these but havent had chance to use it yet as Im trying to get to grips with prime focus AP, but no doubt in the near future Ill be wanting to get this puppy installed. On that basis id be interested to see what your solution was and what the actual issues are

[markarian]

I think if you have the DS version (which your sig says you have) then you should have enough in-focus. That was the main problem with the single speed - and rack and pinion by all accounts.

The problem with the single speed is that you can't actually use a 2" accessory without the 2" eyepiece adapter - which then means you can't focus "in" enough. Very bad design! The inside of the single speed has a lip which is just under 2" in diameter. However, there is sufficient thickness in the wall to allow a lathe to take a little away to make it 2" - very carefully!

[Digz]

That is a pretty poor design. As for taking a lathe to it, your a braver man than me!!!!!

[Mr Spock]

I've just been looking at this to use with my 22mm Nagler. I came to the conclusion that I would need a new focusser...grrr!

[markarian]

Well it was either take a lathe to it or buy another focusser. I thought it was worth the risk - and it paid off. Would have had to spend £120 on a low-profile focusser anyway.

[Deneb]

Don't tempt me! I've only just started imaging at prime focus; I imagine I'll be wanting one of these soon... Already spent enough money recently!

I would have thought the Skywatcher Coma Corrector would be a better match for your 150P DS..

Nadeem.

[Shibby]

I would have thought the Skywatcher Coma Corrector would be a better match for your 150P DS..

Interesting, I've just read your review on it and it sounds good. Maybe on payday

I'm a little unclear how much (or if) extra inward travel on the focuser would be required when attached to DSLR? I think I have about 1 centimetre play left, perhaps a little more...

[adamh]

Shibby,

I'm assuming that you're imaging like me. DSLR, t-ring, the 2" part of the adapter that came with the scope all hooked into the dual speed focuser. Now I've not used a MPCC but I think it screws onto the front for the 2" adapter (like a filter) and goes well inside the focus tube, it shouldn't affect the positioning of the camera.

So if you could focus before you should be able to afterwards - unless the MPCC affects the focus!

Adam

[winterlight]

Is the MPCC any good for refractors?

[markarian]

Adam/Shibby: on my version of the 200P with the single speed Crayford, the MPCC would have to just slot inside the 2" eyepiece adapter (no screw thread there) BUT it would then NOT reach focus with a DSLR. Same would be true of the Skywatcher coma corrector. That was why I had to modify the focusser. Steppenwolf seems to agree.

Can anyone confirm that the new dual speed crayford fitted to the DS versions doesn't need the 2" eyepiece adapter for 2" accessories such as the MPCC? Even if it does it seems to be modified to allow sufficient in-focus for a DSLR.