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24-10-2018, 11:53 AM
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Registered User
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Join Date: Oct 2012
Location: Brisbane
Posts: 131
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Best beginner scope for Planetary Bodies + to attach to Sony Alpha Mount A77
Hi,
I wanted to take some planetary pics (Jupiter, Moon, Mars, let's see..) I will probably pick up a Canon 450D or similar again (what's best, that can be easily and cheaply obtained secondhand?).
I understand a Schmidt-Cassegrain and the Maksutov-Cassegrain would work well. The SCT is great, but hard to get a perfect polish on the lens with? While the Mak is quite forgiving and more consistent - that sounds right?
What equipment will I need to attach it to my camera? Can these be easily connected? Can both be connected easily?
Once upon a time, I had a Borg ED76 connected to a Canon 450D, and got into some very light astro photography.
Any general advice would be great.
I am quite budget limited, perhaps $600 or less (?), and would be buying from the for sale section here. I'm quite patient and prepared to wait for the right thing to come up.
Last edited by Jethro777; 24-10-2018 at 01:43 PM.
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24-10-2018, 03:50 PM
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Local Korean Millennial
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Join Date: Dec 2009
Location: Charleville
Posts: 2,063
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Not sure what you mean by perfect polish on the lens. SCTs are generally more useful just because they can be used for planetary as well as DSO with the correct flattener and they're significantly cheaper to Maks. Do you have a mount already? If so, what is it? this will also determine how heavy your scope can be before it starts to overburden your mount. If you don't have a mount, for $600, you're probably limited to a second hand 8" dob and manually track planets as you record the video with your camera. Altough I'd make sure that the dob you're buying can come to focus with your camera as many are designed for visual use only and does not have enough in focus most of the time without having the primary mirror moved up.
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24-10-2018, 04:38 PM
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Not enough time and money
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Join Date: Aug 2011
Location: Melbourne
Posts: 2,133
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Pick up the Neximage on the classifieds. A small chip will work better than a DSLR.
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25-10-2018, 06:08 PM
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Registered User
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Join Date: Jul 2008
Location: Killara, Sydney
Posts: 4,147
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Hi Jethro.
SCTs are cheap, especially used ones. The starting point for beginners is an 8" or if you are serious a C9.25 or C11. Optically, Celestrons on average tend to be a tad better than Meades (Meade 10" or 12") and the Meade focusser mechanism can be very sloppy.
Cassegrains - RC cassegrains from GSO, the Vixen VMC, or Takahashi Mewlons...
For maks... the choices come down to:
a) Questar 3.5", small, built like a jewel and if money is no object, a Questar 7";
b) Skywatcher f/15 Maksutovs, the 150 or particularly the 180mm, these are bargains compared to Questar, optically most are 9 to 9.5 put of 10, however the downside is you need a decent mount (extra $);
c) Small maks - Meade ETX and various small maks are still in production 90-127mm but really too small to do much on the planets;
d) Meade 7" LX90 or LX200 Maks - obsolete and only a few here secondhand, defork the OTA and throw away the mount;
e) secondhand Intes Maksutov, ideally an M715 or M815, the optics are superb. They are rare but occasionally you can find one on Astromart, if so pounce on it. The point being Intes guaranteed PTV 1/6 wave for the whole scope and for the deluxe models (-D suffix) 1/8 wave, ostensibly perfect.
f) Then there are the dream scopes - the big maks starting with my Santel MK91, and the ones from TEC, AP or APM - 10" all the way to 16. If you have really, really deep pockets. LZOS were ordered to stop production and the last one has been sold by APM but one or two have resurfaced recently on Astromart. But take a very deep breath when you look at the price, these are well into 4 digits. OTOH when you look at the price and size of say a 7" f/10 triplet APO... you can see why people buy a large Mak. Why, ? Well there really is a difference. A good friend (and an ex-SCT user - having tried several) now has an Intes M715D that will easily slay any 8" - 9" SCT for resolution on the planets. Then there is my MK91 which will put a C11 to shame. The MK91 is pure russian unobtainium however, with just 28 made and mine is the only one in Oz. I know of 3 others internationally, and their owners won't part with them.
Lastly there is another option - planetary exotica such as a large schiefspiegler. I recall the 12" f/23 Barry Adcock built in Victoria and the planetary images from that were stunning.
Last edited by Wavytone; 25-10-2018 at 06:43 PM.
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25-10-2018, 06:35 PM
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Local Korean Millennial
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Join Date: Dec 2009
Location: Charleville
Posts: 2,063
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Quote:
Originally Posted by Wavytone
Hi Jethro.
SCTs are cheap, especially used ones. The starting point for beginners is an 8" or if you are serious a C9.25 or C11. Optically, Celestrons on average tend to be a tad better than Meades (Meade 10" or 12") and the Meade focusser mechanism can be very sloppy.
For maks... the choices come down to:
a) Questar 3.5", small, built like a jewel and if money is no object, a Questar 7";
b) Skywatcher f/15 Maksutovs, the 150 or particularly the 180mm, these are bargains compared to Questar, optically most are 9 to 9.5 put of 10, however the downside is you need a decent mount (extra $);
c) Look for a secondhand Intes Maksutov, ideally an M715 or M815, the optics are superb. They are rare but occasionally you can find one on Astromart, if so pounce on it. The point being Intes guaranteed PTV 1/6 wave for the whole scope and for the deluxe models (-D suffix) 1/8 wave, ostensibly perfect.
d) Then there are the dream scopes - the big maks starting with my Santel MK91, and the ones from TEC, AP or APM - 10" all the way to 16. If you have really, really deep pockets. LZOS were ordered to stop production and the last one has been sold by APM but one or two have resurfaced recently on Astromart. But take a very deep breath when you look at the price, these are well into 4 digits. OTOH when you look at the price and size of say a 7" f/10 triplet APO... you can see why people buy a large Mak.
Why, ? Well there really is a difference. A good friend (and an ex-SCT user - having tried several) now has an Intes M715D that will easily slay any 8" - 9" SCT for resolution on the planets. Then there is my MK91 which will put a C11 to shame.
The MK91 is pure russian unobtainium however, with just 28 made and mine is the only one in Oz. I know of 3 others internationally, and their owners won't part with them.
Lastly there is another option - planetary exotica such as a large schiefspiegler. I recall the 12" f/23 Barry Adcock built in Victoria and the planetary images from that were stunning.
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I believe some of your suggestions may be above his recommended budget
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25-10-2018, 06:38 PM
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Registered User
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Join Date: Jul 2008
Location: Killara, Sydney
Posts: 4,147
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Yup... add a nought.
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26-10-2018, 09:01 AM
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Registered User
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Join Date: Oct 2012
Location: Brisbane
Posts: 131
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Thanks for the useful feedback.
Though I'm thinking Schmidt-Cassegrain and the Maksutov-Cassegrain, truthfully, I always had my heart set on a Triplet APO.
I'm going to need to refresh my knowledge and read the Backyard Astronomer again until I know what I want.
I'll post again when I know better what I want.
Thanks so much for helping out! Wonderful community.
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26-10-2018, 07:15 PM
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Registered User
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Join Date: Jul 2008
Location: Killara, Sydney
Posts: 4,147
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Quote:
Originally Posted by Jethro777
I always had my heart set on a Triplet APO.
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In a moment of weakness I did that (130mm f/7 triplet APO, very nice for what it was). Barely lasted 4-5 outings before conceding the mak I had at the time (SW 180mm f/15) beat it on the planets easily and was the scope that was used, every time.
Small fast refractors do have a place - wide-field imaging. But as planetary scopes - not good - its all about focal length (6m or more) and razor sharp optics which means significant aperture ... unless you have an observatory big enough for a 7" APO, better off sticking to SCT or maks.
Last edited by Wavytone; 30-10-2018 at 01:07 PM.
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27-10-2018, 06:10 AM
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Registered User
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Join Date: Mar 2018
Location: Sydney
Posts: 227
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I have a triplet APO and it’s great for imaging DSO’s but I don’t even bother with it for planets.
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30-10-2018, 11:49 AM
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Registered User
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Join Date: Oct 2012
Location: Brisbane
Posts: 131
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Thanks for all that, I am going to start with DSLR Astrophotography to start with. That will be nice. I'll see what I can do with what I have first.
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