C11 much better than 180 Mak?

[philwright66]

Hi all,

i am the proud owner of a skywatcher 180 pro maksutov,which i use mainly for imaging planets. i am wondering if the extra aperture and resolution of a celestron 11 would make a noticeable difference to my images. i am very pleased with the images my 'scope produces,but crave even better! i use a cg5 mount which just about copes with the heavy 180,so maybe a c11 would be 'ok' on it as well. or alternatively,i could get a g11 or similar heavy duty setup.

attached is my best saturn image so far(from last year),to show how my mak performs.

cheers,phil.

[riklaunim]

In theory yes But you will need seeing or some accessories to use higher resolutions efficiently and often.

[JamesF]

I'm sure people have said that the C9.25 is better for planetary photography than the C11, but I can't for the life of me recall why.

James

[riklaunim]

I'm sure people have said that the C9.25 is better for planetary photography than the C11, but I can't for the life of me recall why.

James

Well, there is no point why it should be better by default

[ollypenrice]

Damian Peach's website discusses the Celestrons. From memory he says that the C9.25 runs the C11 close. I guess you need great seeing to exploit more aperture, hence taking a C14 to Barbados.

Olly

[JamesF]

Damian Peach's website discusses the Celestrons. From memory he says that the C9.25 runs the C11 close. I guess you need great seeing to exploit more aperture, hence taking a C14 to Barbados.

Olly

That does seem to be the general experience. There's also the issue of cooling time and response to changing temperatures over the course of a session. AFAIR with the C14 Damian Peach basically said "don't even bother if you can't keep this scope outdoors".

Never mind the hyperstar. What they really need is a fastar-compatible cooling fan

James

[chuenmanc]

For visual, my CPC1100 showed greater colour than my 7" mak, but the mak was a little sharper. Not sure if that has any relevance to imaging though!

[philwright66]

Thanks everyone for the interesting replies. Maybe i should concentrate on getting the best out of the Mak,using better ccd imagers such as the new 618 Imaging Source cameras. I feel that the 180 Mak is very sharp visually,so it may be just a case of taking advantage of better seeing conditions as and when they occur. I,m thinking that if i forked out £1.5k or so on a C11, and the images obtained were not noticeably higher resolution due to atmospheric issues affecting larger apertures more,then i would be very disappointed!

Cheers,Phil

[riklaunim]

The bigger your scope is the better imaging chain you will have to have So it's a good idea to upgrade cam first. You can also look at things like atmospheric dispersion correctors which fix color dispersion caused by atmosphere on low alt objects (like Saturn is - and will be even lower). If the dispersion is fixes it's possible to shoot plain L channels (ir/uv cut) without loosing sharpness. As this channel is very bright - you get short exposure and low gain.

If you are looking for cheap used SCTs then you can look at USA market - there is a very big SCT resale market (from very old to quite new).

BTW C11 can do things like:

http://www.rkastrofoto.appspot.com/site_media/astro/orig/saturn-11-05-2011/2qqlong-rgb-2030.png

http://www.rkastrofoto.appspot.com/site_media/astro/orig/saturn-21-04-2011/1-rgb-2147.png

http://www.rkastrofoto.appspot.com/site_media/astro/orig/saturn-15-04-2011/f43-lng610-2211.jpg

http://www.rkastrofoto.appspot.com/site_media/astro/orig/saturn-13-02-2011/10ir-ch4_ir_red-0019.jpg