TAL 200k or Celestron C8-s?

[applecounty]

I am new to SGL so first things first - 'hello'

We (the family) are thinking of purchasing either a Celestron C8-s or a TAL Klevsov 200k. The aim is to have something a little more portable than our Orion (UK) Newtonian 10 inch, to take to our Observers Society meetings. We would like something that would be equally at home doing Astro photography and Observing.

Aside from the Tal’s optical and construction reputation (It probably requires more attention to what it is mounted on and I am familiar with Soviet era photography kit), and from what I have gleaned from a gent in Northern Ireland via email, I know nothing of the TAL’s reputation in the field. On the other hand, the Celestron product has a well documented pedigree, with plenty of information available on the web.

I would appreciate some feedback from SGL members on which scope , in their opinion, would give us most enjoyment.

[Helen]

Hi, and welcome to SGL!

I've got a C8 - the Nexstar fork mounted GPS version - and I really love it. Because of the fork mounts its heavier than an OTA, but I can lift and carry it around (and I'm only just over 5 foot and not very muscular!). But that is the price you pay for great mechanisms and a very easy to use set up. For visual it is great in Alt Az, and alignment is very quick and easy. For imaging, with the appropriate barlows and focal reducers, its a very flexible set up - last night I used mine to image the comet (with an f3.3 reducer and a CCD), then the Orion Nebula at native f10 with a DSLR, and then ended the night with a 2.5 barlow and a toucam on Mars! I'll be posting the results later.

For an idea of what an imager starting from scratch can achieve with a C8 then see Martin's for sale post (which is an amazing deal by the way!)

http://stargazerslounge.com/index.php/topic,18872.0.html

I have no experience with the Tal, but I'm sure Kaptain Klevsov will be along shortly...

Helen

[John]

I think I would go for the C8 over the TAL 200K. I've owned a C8 and they are great scopes. The TAL's also have a good reputation but I have heard that they can be difficult to collimate due to the optical design which is different from the C8.

John

[Kaptain Klevtsov]

The Tal might be difficult to collimate, whereas the C8 isn't. The reason for this is that nobody ever has to bother collimating a Kletsov 'scope so nobody has done it so far. Its a Maksutov with spherical surfaces, so the mirrors and lenses don't have the same optical centre issue as non-spherical surfaces.

Never having had a C8 I'm guessing here (like John is) so I'm just adding biased guessing.

If you get a C8 you can improve it by buying a Crayford to add on the back, with the Tal, it comes with one on already (the newer ones that is, the older ones had a very short travel R&P focuser). Mirror shift isn't a problem as they're fixed.

The Tal is supposed to give a coma free wide flat field, allegedly better than an SCT, I've not had bother with it.

If you have any specific questions, please feel free to ask.

Kaptain Klevtsov

[applecounty]

Thank you for your suggestions.

I am assuming it is correct to treat these two instruments as broadly comparable?

[John]

..... Never having had a C8 I'm guessing here (like John is) so I'm just adding biased guessing.

Darn - you got me there KK. :D

I really like TAL scopes - had a TAL 100R when they 1st came out and I used to be a regular subscriber to the Talscopes Yahoo group which is where I picked up the possible issues with Klevtsov collimation - but they do like to tinker with their scopes a lot that lot - too much probably

John