Results 1 to 4 of 4
Like Tree2Likes
  • 1 Post By jerryTheC
  • 1 Post By jerryTheC

Thread: Good, Possibly Older, 8"+ SCT'S?

  1. #1
    andro-mike-eda's Avatar
    andro-mike-eda is offline Banned
    Points: 13,242, Level: 79
    Level completed: 41%, Points required for next Level: 208
    Overall activity: 0%
    Achievements:
    2 Posts Achievement20 Posts Achievement!50 Posts Achievement!5 Threads Achievement!Ghost Achievement! Averaging 5+ posts a day!
    Join Date
    Jan 2013
    Location
    NE TX, USA, Earth, Orion Arm, Milky Way, Local group
    Posts
    1,845
    Points
    13,242
    Level
    79
    Thanks
    868
    Thanked 433x 306 Posts

    Default Good, Possibly Older, 8"+ SCT'S?



    What is good? To be avoided?

    I've owned a 5" Celestron, circa 1980, and the optics weren't the best, but not against one of that vintage, might like it.

    Anything else to look out for, like thorium oxide glass or other health concerns?


    I don't want to need power, I observe from the middle of nowhere.

    What sort of mount, etc?

    I was planning on a dob, perhaps I should look at SCT's. Thoughts?
    Last edited by andro-mike-eda; 07-06-2014 at 08:19 PM.

  2. #2
    jerryTheC's Avatar
    jerryTheC is offline Super Moderator
    Points: 26,972, Level: 100
    Level completed: 0%, Points required for next Level: 0
    Overall activity: 11.0%
    Achievements:
    365 Days+ Registered Achievement!50 Posts Achievement!5 Threads Achievement!200+ Posts Achievement!First 1000 Experience Points
    Join Date
    Apr 2011
    Location
    Harrow, UK
    Posts
    6,032
    Points
    26,972
    Level
    100
    Thanks
    335
    Thanked 1,915x 1,623 Posts

    Default

    Have a look at uncle rod's used cat guide - it's a great resource for finding out about older SCTs.

    I think the standard celestron OTAs have stayed more or less the same - though the coatings have probably changed over the years; I know that when I got my N11GPS there were two versions available - one with better coatings and different glass for the corrector plate.

    As far as the mounts go, I find an alt-az mount keeps the eyepiece in a much more convenient position than an EQ mount does - so for visual use, the alt-az gotos are great.

    But if you want an unpowered mount, then there's a trade off - do you go for the easier tracking of an EQ, or the more convenient eyepiece position of an alt-az.

    For a manual alt-az mount, I favour the T style ones like the one in my avatar pic over the traditional alt-az mounts - and personally, I much prefer the dob style ones without slow motions.

    That said, I've never used an older manual fork mount (did they ever make a completely manual one?)
    andro-mike-eda likes this.

  3. The Following User Says Thank You to jerryTheC For This Useful Post:

    andro-mike-eda (07-07-2014)

  4. #3
    andro-mike-eda's Avatar
    andro-mike-eda is offline Banned
    Points: 13,242, Level: 79
    Level completed: 41%, Points required for next Level: 208
    Overall activity: 0%
    Achievements:
    2 Posts Achievement20 Posts Achievement!50 Posts Achievement!5 Threads Achievement!Ghost Achievement! Averaging 5+ posts a day!
    Join Date
    Jan 2013
    Location
    NE TX, USA, Earth, Orion Arm, Milky Way, Local group
    Posts
    1,845
    Points
    13,242
    Level
    79
    Thanks
    868
    Thanked 433x 306 Posts

    Default Re: Good, Possibly Older, 8"+ SCT'S?

    I feel like I should get an eq if I decide to get an SCT, for AP, but I mostly do visual, so the better positioned ep is appealing. I might need power to run an eq for ap, anyway, D batteries might not be bad, but I'd hate to drag a car battery around.


    I'd think that the coatings have improved but I think I could see almost as many dso's as in a new one. And the older ones appeal to me.

    So I'd need a mount and rings in addition to the OTA? I'm not familiar with the mounts mine was on a photo tripod.

  5. #4
    jerryTheC's Avatar
    jerryTheC is offline Super Moderator
    Points: 26,972, Level: 100
    Level completed: 0%, Points required for next Level: 0
    Overall activity: 11.0%
    Achievements:
    365 Days+ Registered Achievement!50 Posts Achievement!5 Threads Achievement!200+ Posts Achievement!First 1000 Experience Points
    Join Date
    Apr 2011
    Location
    Harrow, UK
    Posts
    6,032
    Points
    26,972
    Level
    100
    Thanks
    335
    Thanked 1,915x 1,623 Posts

    Default

    With SCTs, there's usually either a fixed twin arm fork mount that the OTA is permanently attached to, or for EQ or other mounts, the OTA is usually removable and attaches by a dovetail bar. While you probably could do something with tube rings, which is the usual thing for refractors and newts, the normal practice is to bolt the dovetail bar directly to the SCT OTA - usually, the OTA has front and rear castings bolted to the main tube, so you can attach a dovetail just by using existing holes with longer bolts. The mount has a dovetail holder (aka saddle) that clamps onto the dovetail to hold the OTA in place (and you can move the dovetail along to balance the scope).

    The fork mounted scopes usually bolt to a tripod or wedge.
    andro-mike-eda likes this.

  6. The Following User Says Thank You to jerryTheC For This Useful Post:

    andro-mike-eda (07-07-2014)

 

 

Similar Threads

  1. My fancier more expensive eyepieces aren't as good as my older ones
    By nemesis256 in forum Telescope Eyepieces Forum
    Replies: 16
    Last Post: 09-19-2013, 12:56 PM
  2. Older Meade 2X Telenegative Amplifier - any good?
    By precaud in forum Astronomy Beginners Forum
    Replies: 5
    Last Post: 11-27-2012, 10:14 PM
  3. Best choice for "older" relative with bad back (urban)
    By nialljcampbell in forum Astronomy Beginners Forum
    Replies: 7
    Last Post: 06-29-2012, 08:47 PM
  4. Are Older scopes as Good as New ones?
    By theVenerable in forum Telescope Forum
    Replies: 15
    Last Post: 08-20-2011, 01:17 AM
  5. Replies: 1
    Last Post: 12-11-2008, 09:01 PM

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •  
Powered by vBulletin® Version 4.2.0
Powered by vBulletin®
All times are GMT. The time now is 07:42 AM.