Upgrades or buy new? Advice for relative newbie please.

[mhc]

Folks,

New member and relative astro newbie here. I've trawled the archives and picked up lots of advice, but now need to actually post a question <gulp>.

I have a (very) old Orion SX-150 6" Newt on a heavy pedastle with EQ mount, 25mm and 9mm Vixen Super Plossl eyepieces and Barlow. I received all this (gratis!) about 4 years ago, and it had been sat in the previous owners shed for many years before that.

While it works, I have some usability issues and seek advice.

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  [li]The rig is rock solid, but completely ungeared. One has to push/pull to move, no slow-motion controls, etc. What sort of replacement mount would be suitable for a 6" Newt? Can one purchase a mount without legs, since I'm guessing that the pedastle will be more rigid than a tripod? I've seen EQ5 mounts second hand for ~£200, but new 6" scopes for less! I've also considered building my own Dob mount for ease of use
  [/li]
  [li]The rack and pinion focuser is quite "gritty". I've not yet tried to dismantle and clean it (if possible), but how worthwhile would a Crayford be on a 'scope of this age and modest size? They seem to cost ~£80?
  [/li]
  [li]The mirror looks filthy! I've read lots on cleaning it, bought the soap flakes, distilled water and cotton wool, but not braved it yet. I'm nervous about collimation, especially as I can't see how to adjust the secondary.
  [/li]
  

Given that I can get a new 8" Dob (Skyliner or the Telescope-Service.com versions) for <£250, 10" < £350, are the above upgrades worth it or am I better off buying new?

Please don't take the above "criticisms" as me being ungrateful. I'm truly not. I LOVE this stuff. My 1st sighting of Saturn on the night I 1st got the scope (with my father-in-law balancing the OTA because we couldn't work the mount!) blew me away, but I know I can do better. I'm also a self-confessed gadget freak.

Apologies for such a long post.

Best wishes,

Mark

[geppetto]

Mark

I would be inclined to give the old scope some TLC.

You can get plenty of practice and rid the gremlins of mirror cleaning

and collimation without risking too much.

The focuser should clean up nice with a re grease

The collimation bolts might be hiding behind a protective plate at the mirror end.

If the mirror surfaces are sound after a good clean then it will have a lot more

milage in it

[GordonCopestake]

If the 'scope you have is an Orion Optics (UK made) telescope then you have an excellent set of optics. Take a look at their webpage at www.orionoptics.co.uk. If however you have an Orion Telescopes (USA) telescope then it is a rebranded chinese telescope made by Synta (www.telescope.com). I believe that you have an Orion UK 'scope and if this is the case then you will want to hold on to it as few manufacturers match the optical quality of the optics made by Barry Pemberton at Orion Optics. Depending on budget you can have a CG5-GT mount brand new for about £430 from David Hinds or a manual Vixen GP mount from Orion Optics for £364. Looking on the second hand market I would look for a dual drive EQ5 which can be had dor about £200 as you say. Although given the weight of your OTA you could probably get away with an EQ3/2. A few photos would help identify the 'scope. You can easily change the focuser if you are happy with the optics. As for cleaning given the age of the 'scope it's probably a good idea (not often I say that!) if you can, remove the entire mirror cell from the OTA and dump the lot in a bath of distilled water with a drop of IPA in it. Use CLEAN LINT FREE cotton wool or an optical cloth to wipe in straight lines from the center to the edge of the mirror. Never use the same piece of cotton wool again as you can drag grit across your coatings and cause scratches. Be brave! Mirrors are delicate, but actual less fragile than most people think. Let us know how you get on!

[mhc]

Thanks for the suggestions.

I had previously checked the web for info on the 'scope, and found a single reference with no practical information.

I couldn't register with Isee to upload pictures, so I've posted them here: http://photos.mhc-online.co.uk/scope

I'm interested to learn anything about the orgins of the scope.

Regards,

Mark

[GordonCopestake]

Hmmm, not seen one of those before, but as it has Vixen green triming I am inclined to believe that it IS an orion optics 'scope. Perhaps an email to barry at Orion Optics would solve the mystery.

[mhc]

Thanks Gordon, I'll give it a try.

[nitram100]

Yeh thats an Orion Optics scope, i remember the old SX range, i have an Orion Optics scope aswell, definately hold on to it.

[SteelRat]

Looks tidy too 8) Hows about a pic of the mount?

[mhc]

Nitram - Thanks for the confirmation. Any idea if/how the secondary can be adjusted? And, pardon my ignorance, but why is it such a keeper? I understand that the Orion Optics instruments are highly regarded, but surely modern mirror coatings, etc, have improved much over what is probably a 10 year old scope? :?

SteelRat - Sure. Will probably post a picture later tonight, weather permitting.

[nitram100]

Hi mhc, i'm not too sure how you would adjust the secondary on that scope but im sure john or barry at orion optics would tell you, or you could join the orion optics yahoo group at www.egroups.com.

I have had a 10" Europa f4.8 for about 10 years now and it still blows away any skywatcher telescope of the same aperture that i've looked through and thats with the standard optics that came with it, so the optics are very special indeed and worth holding onto, as far as i can remember, when i was looking for my first real scope and narrowed it down to Orion Optics, the SX range was of higher quality than the Europa, it then became the DX or GX range i think, which came with a green coloured pedestal mount.

Heres a pic from the GX range, which looks very similair to your SX scope.

http://www.jwebdale.btinternet.co.uk/

If i was in your position, i would definately hold onto the Orion, maybe even get it recoated with hilux coatings by orion optics, which would cost about £85 and you'd have a cracking scope.

They are doing a great deal on a good mount at the moment,

http://www.orionoptics.co.uk/acatalog/Mountings_and_Fittings.html

[mhc]

Thanks for the explanation.

I've added some pics of the pedastle mount to the bottom of this page: http://photos.mhc-online.co.uk/scope

It's very heavy, rock solid but rather primative. No fine controls. In fact, no controls at all

[GordonCopestake]

Something like a Vixen GP or CG5 would suit your 6" well. Depending on budget a HEQ5 would also allow an upgrade path should you wish a larger scope in the future.

[nitram100]

Thats an Orion Optics MKII mount if remember correctly, they made them themselves, before importing vixen mounts etc, it does look pretty solid!

[mhc]

Oh, it's solid alright, as my shins and toes can attest

Am I correct in thinking that if I bought an EQ5 (or similar) I should try to use my pedastle instead of a tripod? Just take the mount head (correct term?) and (somehow) bolt it to the pedastle.

I've been trawling the 2nd hand ads. Does this look reasonable?

http://www.astrobuysell.com/uk/propview.php?view=11591

I like the idea of motor drives, as I have delusions of astrophotography. Would make a nice counterpoint to my macro photography

Probably another dumb question, but are the Vixen GP and CG5 mounts noticably better?

Thinking ahead, would the EQ5 support an 8" reflector? How about a 10"? (dreams are everything!)

Thanks for all the help,

Mark

[GordonCopestake]

If you are looking to upgrade to a 10" reflector at some point I would say jump straight to the HEQ5. It's more expensive than the EQ5 but it's much cheaper than having to buy another mount later down the line. The mount is the most important part of your setup.