Since the few years I have been busy with amateur astronomy I have owned several scopes and several types of scopes. What follows is based on personal experience and is not perse an authoritative review of the telescopes mentioned. I'll keep this simple and just go through the telescopes I have owned one by one. For each scope I will try explaining why I'd buy it again.
Meade ETX-70 / Meade ETX-80
This scope I would buy again. If you do not already own a telescope it would be a good starter scope in my opinion. I think, that the main advantages for a starter are the fact that it is highly portable and the fact that you can use it without knowing too much about 'the skies'. Portability is good, you can have the scope up and running in a matter of minutes after some practice. And once you have it up and running it's built-in goto computer will be your tour guide and not only show you the heavens, but it will even tell you about them.
What you should know is that the ETX is a short-tube and that because of this it will give you a wide field of view. This property is excellent for observing many deep-sky targets, but it will allow you to observe the moon and planets as well.
LOMO Astele 70 Maksutov OTA
This little telescope is everything the Meade ETX-70 and 80 are not: It is not a lens telescope but a combination of lenses and mirrors. It's not made of plastic, it's built as if it is supposed to survive a tank running over it. It is not American, it's Russian. Rather than being offered in every super market the Astele is hard to find (I suspect they are trying to avoid to sell as good as they can). And this is basically why I bought it. It's also very small and together with a tripod I can virtually bring it every where I go. I would buy this scope again, or even the 90mm variant if it would be available.
Meade DS-2130
This scope I would never buy again and as we speak it has been 'decommissioned'. I do however still own and use the goto mount with the Astele 70 and the ETX-90. The mount is very nice and durable when compared to the ETX-70/80.
The DS-2130 is advertised as a Newton type telescope (which means mirrors only, no lenses) but strictly speaking it's a catadioptric telescope or compound telescope. It combines a primary and secondary mirror with a little lens built into the focuser. The reason I bought this scope was aperture (130mm) so I would be able to 'detect' fainter deepsky objects than with the aperture limited ETX-70/80 and Astele. But frankly speaking I have hardly seen anything at all with this scope. The 'problem' with Newton scopes is that you need to collimate them - that is lining up the mirrors and the focuser. And the problem with the DS-2130 is that it makes this relatively simple process overly complicated due to the little lens I mentioned earlier. I have made many modifications to this scope (focuser, made lens removable, replaced the spider which holds the secondary mirror) only to find the images very disappointing.
Meade ETX-90 OTA
For new comers: OTA means 'optical tube assembly', so no mount and no tripod. I purchased it that way second hand and I only purchased because it was included with a bunch of Meade 4000 series and some WA oculairs. But the scope is very nice and I use it on the DS-2130 mount or even as a secondary scope on my LDX75 mount.
Shortly after I purchased this scope I saw a second hand modified Canon EOS 1000d for sale and I did my first astro photography experiments with the ETX-90 and a Meade 6.3 focal reducer.
Home built 125mm f/5.2 short tube achromatic refractor
With the DS-2130 being of no use I still had the desire for some more aperture mainly for deepsky and wide field observing. In between the ETX-90 and this scope I also acquired a Meade LDX75 equatorial mount. So when I saw this 125mm achromat offered I decide to purchase it. As expected this scope shows bright blue halos around bright objects. So although this scope is brilliant for wide and deepsky views, photographically it is severely handicapped.
It is currently configured as a Petzval using the secondary lens that came from a William Optics 66 ED Petzval which I purchased later. It still needs some work though.
I would buy this scope again.
William Optics Zenithstar 66 ED Petzval semi-APO
This scope I would not buy again, I have got nothing but frustration with it. My main complaint is with the coatings, they came off by simply looking at them. As it was no longer produced I could not swap it for another one and against better judgement I decided to keep it. Now Petzval design (2 doublet lens groups) implies that you get flat fields but I soon found out that this isn't the case with this Petzval. For improving flat fields I made modifications to the scope as they are described in the Yahoo William Optics group.
Astro-Professional 102 ED semi-APO
After all past experiences I decided I wanted a scope that I could actually use out-of-the-box, visually and photographically, and with decent aperture for a modest price. If I would start again with all current experience, and with a budget that would allow me to buy a LDX75 mount and the Astro-Professional 102 ED, I would buy this scope straight away and skip the rest. Which means I am pretty pleased with it.
BTW, the scope is also offered under many different brands, so what I write here also goes for the Orion 102 ED Premium, the William Optics Megrez 102 ED, and AstroTech 102 ED. And I am sure I can come up with a few more that are based on this exact same scope.
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