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View Full Version here: : Which Cassegrain


keppar
22-11-2008, 06:38 PM
I,m looking for a scope to compliment my megrez 90 APO
It will sit side by side in a observatory on a eq6. Due to money constraints. I have narrowed it down to a Celstron C8 SGT or a sky watcher PRO mak 180 ,both are $1699 which is my cash limit. What are your thoughts ,Ideas or suggestions
Could you also also explain the difference and benifits between a .Schmidt-Cassegrain and a Maksutov-Cassegrain
Thanks

keppar
22-11-2008, 06:44 PM
Opps forgot to mention will be used for astrophotography

dannat
22-11-2008, 06:57 PM
I think mak's have all spherical surfaces.corector.primary & secondary where as a SCT have a strange curve which is more difficult to get right in the corrector.
However mak's usually have a longer f ratio which makes them heavy & expensive when you get to bigger sizes so you don't see many above 4-5".
Also because of the curved corrector of the mak(thicker), cool down times will be increased.
In theory i think mak's give sharper images..it probably depends on the company making the product
I am very happy with the sharpness of my 5" mak,

Wavytone
22-11-2008, 08:16 PM
Stay away from f/15 Maks, they're too slow.
Opt for f/10 to f/12 if its Maksutov or a Meade 8" SCT.

I think you will be disappointed by the chinese 180mm Maks compared to a Meade 8" SCT.

AlexN
23-11-2008, 05:06 PM
The Intes Micro Mak's are good/great units if you can find one... As far as price/performance, you will find it hard to beat a 2nd hand Meade or Celestron 8" SCT.

These quite regularly hit the for sale section of the forums for less than $1000, usually with plenty of extras..

keppar
24-11-2008, 10:34 AM
Thanks all

keppar
24-11-2008, 10:34 AM
Thanks all
:thumbsup:

Kal
24-11-2008, 10:42 AM
I think the 8" Schmidt will be the better choice for the following reasons:


More versatile imager with F/6.3 and F/3.3 reducer/correctors
native F/10 is more workable for deep sky
1" larger aperture