Hi Robz,
Les has done 2 great posts on the aspects thet need to be considered.
On the practical side it really comes down to how much budget and how many compromises you want to make.
I had a really nice US made 8" Meade SCT and a great CPC1100. I also had a very nice 4" refractor (though not as good as the Tak or AP refractors).
MY refractor gave me really nice sharp contrasty views and was simple and easy to setup and did not take much effort to maintain. Due to the lower aperture I found that it's performance on DSO's was lacking but it was a nice scope.
My 8" Meade was very easy to move around and setup. It also performed well across the board but images were "soft" and not as contrasty as the refractor.
My CPC1100 was an improvement on the Meade but again planetary views, while signficantly improved, were a little soft for my taste. Also the CPC1100 was heavier and took ages to cool down to ambient (over 2 hours). Once you get to this size SCT and above you really need to consider cool down times and mechanisms to help reduce this like filtered active fans/vents. As I did not have these, I used to setup my CPC1100 hours ahead of my visual sessions.
Both my Meade and CPC1100 held their collimation quite well so I did not personally find this a problem. Focus is an issue in both of these so I would consider a focuser upgrade mandatory.
When I first used a Mewlon 250 this scope blew away any of my prior scopes in terms of sharpness and contrast. The Mewlon 250 is also easy to setup and use at a reasonable price for the quality you get.
I now have a Mewlon 300 which completely blows away anything else I have used or owned. However, It can be a pain in the behind to setup and breakdown as the total setup weighs nearly 100kg but it is a sacrifice I am happy to make.
For Visual image quality/sharpness/contrast standard SCT's come nowhere near the Mewlons or similar Quality APO's and Similar Quality reflectors.
I have found focus on the Mewlon 300 to be very easy as it has a motorised secondary and the primary is permanently fixed. Also you really have to bounce these around to mess up your collimation.
Another critical thing I have learnt is quality of both the mount and tripod especially for portable systems. The last thing you want is a very high quality scope were the image jiggles around at the slightest touch or breeze. You can very quickly become frustrated.
- Get the best quality Mount AND Tripod you can afford
- Get the best quality Optics you can afford
- Get the best quality mechanical setup you can afford (ie structural rigidity/alignment, baffling etc)
- I would not try to choose a VISUAL scope based on Astrophotograhic images. Base your decision on real visual testing if you can.
- Go and watch other users setup and breakdown their systems at starparty events to gauge if this suits your circumstances.
Cheers
Quote:
Originally Posted by ngcles
Pt 2 ...
I can't (and won't) tell you what to feel and if these are your feelings, a Newtonian is probably not for you and there is nothing wrong with that at all.
Don’t for a moment think I’m ridiculing your choice – I’m not. All I hope is that you choose for the right reasons. There are many reasons that make the Schmidt-Cassegrainian a legitimate choice for many people. No argument there at all. Going down that path because you hope for better visual planetary images is not one of them. Going down that path because you believe you are guaranteed higher quality optics … ditto. Some people also go down the S/C path because of peer-pressure or because they find them aesthetically pleasing (ie pretty). Personally I don’t buy telescopes to look at, but if that’s important to you as a buyer, well that’s your choice and I won’t argue about your feelings. Personally I choose a telescope based on what it’s like to look though, not look at!
Very best of luck with your choice and I sincerely hope that whatever you settle on, it will bring you many hours of observing pleasure.
Best,
Les D
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