Page 2 of 2 FirstFirst 12
Results 11 to 19 of 19
  1. #11
    OleCuss's Avatar
    OleCuss is offline Curmudgeon
    Points: 61,950, Level: 100
    Level completed: 0%, Points required for next Level: 0
    Overall activity: 38.0%
    Achievements:
    200+ Posts Achievement!First 1000 Experience Points400+ Posts Achievement365 Days+ Registered Achievement!Got three Friends
    Join Date
    Oct 2010
    Location
    Central California, USA
    Posts
    12,092
    Points
    61,950
    Level
    100
    Thanks
    2,215
    Thanked 5,447x 3,561 Posts

    Default



    Quote Originally Posted by Bob327 View Post
    I would do a simple star test onteh OTA as it stands now, dirty and with a flakign mirror....if it star tested terrible then I would sit down and thing about havign it re coated BUT if it star tested fairly good after collimation to be honest I seriously doubt a little flaking will be very bothersome...But please do not expect anything out of using the 7 mm eyepiece you found with the scope...heck it would be too powerful on most nights even on a brand new C8

    Bob G
    I think your advice is good - but I might not take it .

    I don't like the way the mirror is and the fact that it has deteriorated to me means it will likely continue to do so. It may just be foolish irritation on my part, but I want a really nice mirror in the thing.

    With two outfits in driving distance which do coating for around $40-70 (and up), if I can figure out how to take the baffle tube and focuser assembly off the mirror (and maybe put it back on. . .) I think I'll take a shot at getting it re-coated.

    So far I've not found a good write-up on how to strip the appliances off the C8 mirror and how to put them back on - but I figure I need to check out Cloudy Nights a bit more on that question.

    Edit: I ran into a post on a Cloudy Nights forum which said that you lose about 0.5% reflectivity every year. So if you start from what was an original coating reflectivity of 89% and figure that the 'scope is about 25 years old - you've got a reflectivity now of about 76.5%. Figure the same loss for the secondary mirror and you've got a substantial degradation of reflectivity. Net effect should be that if I get an enhanced coating done of both the primary and of the secondary - I should likely double the effective light-gathering capacity of my 'scope. If you figure that I've also got a deteriorating coating (disturbingly obvious deterioration) it seems likely that I'll improve my particular 'scope even more than that.

    Net effect is that if I can figure out how to do it well, I'm going to get at least the primary re-coated.
    Last edited by OleCuss; 11-22-2010 at 04:15 PM.

  2. #12
    OleCuss's Avatar
    OleCuss is offline Curmudgeon
    Points: 61,950, Level: 100
    Level completed: 0%, Points required for next Level: 0
    Overall activity: 38.0%
    Achievements:
    200+ Posts Achievement!First 1000 Experience Points400+ Posts Achievement365 Days+ Registered Achievement!Got three Friends
    Join Date
    Oct 2010
    Location
    Central California, USA
    Posts
    12,092
    Points
    61,950
    Level
    100
    Thanks
    2,215
    Thanked 5,447x 3,561 Posts

    Default

    An update in case it should prove useful to anyone. I talked with O.W.L. and did a bit of checking on-line. They seem both helpful and knowledgeable. And for someone who has never before played in the guts of a telescope they offer a nice service I believe they call their "Silver Service". For $280 they'll take the whole scope, disassemble the thing, re-coat, and make sure everything is put back together right and properly aligned. For $115 they'll take the mirrors and re-coat them but I do the disassembly and assembly.

    They seem like a good outfit and I'll likely go with them. Not yet sure which service I'll use.

  3. #13
    jb32828's Avatar
    jb32828 is offline Bright Giants
    Points: 10,393, Level: 70
    Level completed: 48%, Points required for next Level: 157
    Overall activity: 0%
    Achievements:
    10 Days registered200+ Posts Achievement!First 1000 Experience Points365 Days+ Registered Achievement!400+ Posts Achievement
    Join Date
    Apr 2010
    Location
    Orlando fl
    Posts
    572
    Points
    10,393
    Level
    70
    Thanks
    90
    Thanked 258x 158 Posts

    Default

    Like Bob says, I would first put a 32mm plossl eyepiece in it and see how it looks before doing anything. I know that it might look "bad", and it might bug you, but our club has a 51 year old Criterion RV6 that has a primary that looks pretty rough but it still makes for some really good views.

    You got a 1nearly free scope, I would tKe advantage of it and keep it as cheap as possible to learn on...you Re gonna be able to see plenty with that scope and it will last you while you save for a nice one.
    --- Jason ---
    Meade SN-6,
    To view links or images in signatures your post count must be 5 or greater. You currently have 0 signatures.
    XX12g, Orion ST-80
    Atlas EQ-G
    Nagler 9T1, 12mmT4, 17mmT4, Panoptic 22
    Canon 60D, Blue Fireball 2" EOS Adapter, Astronomik CLS LP filter

  4. The Following User Says Thank You to jb32828 For This Useful Post:

    OleCuss (11-23-2010)

  5. #14
    Tombstone17's Avatar
    Tombstone17 is offline HYPER GIANT
    Points: 18,068, Level: 92
    Level completed: 92%, Points required for next Level: 32
    Overall activity: 0%
    Achievements:
    10 Days registered200+ Posts Achievement!First 1000 Experience Points365 Days+ Registered Achievement!Got three Friends
    Join Date
    Oct 2009
    Location
    So. Cal. near Disneyland
    Posts
    2,938
    Points
    18,068
    Level
    92
    Thanks
    1,843
    Thanked 526x 471 Posts

    Default

    400 Bucks for a rebuilt C8 is still not bad. If everything else works I would say go for it oldcuss.....the important thing is if your happy with it and don't let anybody tell you other wise..
    Enjoy the Black cause they can't take it back............
    To view links or images in signatures your post count must be 5 or greater. You currently have 0 signatures.
    Stoney
    Meade LX90-8" ACF, Meade DS 2090 AT, Cannon450 Rebel, US Navy made 10x50"
    <a href=http://cleardarksky.com/c/AnaheimCAkey.html>

    To view links or images in signatures your post count must be 5 or greater. You currently have 0 signatures.

  6. The Following User Says Thank You to Tombstone17 For This Useful Post:

    OleCuss (11-23-2010)

  7. #15
    OleCuss's Avatar
    OleCuss is offline Curmudgeon
    Points: 61,950, Level: 100
    Level completed: 0%, Points required for next Level: 0
    Overall activity: 38.0%
    Achievements:
    200+ Posts Achievement!First 1000 Experience Points400+ Posts Achievement365 Days+ Registered Achievement!Got three Friends
    Join Date
    Oct 2010
    Location
    Central California, USA
    Posts
    12,092
    Points
    61,950
    Level
    100
    Thanks
    2,215
    Thanked 5,447x 3,561 Posts

    Default

    Quote Originally Posted by Tombstone17 View Post
    400 Bucks for a rebuilt C8 is still not bad. If everything else works I would say go for it oldcuss.....the important thing is if your happy with it and don't let anybody tell you other wise..
    Thank you. As I see it, once O.W.L. is done with it the thing may actually be better optically than when it was brand new.

    What's more, I really may never get a bigger scope than this one if I get the thing working well. It's a decent sized piece of glass and is still nicely portable. But if I don't get it working really well I'll feel the need to get a newer and likely much more expensive telescope next year. If I really pushed the issue with my wife I could probably get something like a C11 or a C14 next year - but a decent 8 incher should probably be enough for me to explore with for a year or two (or maybe a decade or two).

    Maybe I'll get a 12 inch GOTO Dob some day - but I really may stick with my little C5 and the C8. And if I need to mate the C8 to a modern mount, after all the coaching I got for the C5 I'm pretty sure I can make that work as well.

    I'm still a happy man - and I do fully intend to get it recoated. No pictures, but there are likely more than 100 mostly linear areas of disruption of the coating. You can see flakes on the inner aspect of the tube. Personally, I think the initial coating job was defective and if it's not recoated now I'll soon have to do it anyway.

    But with a high quality coating on the thing I should be pretty happy for years.

  8. #16
    OleCuss's Avatar
    OleCuss is offline Curmudgeon
    Points: 61,950, Level: 100
    Level completed: 0%, Points required for next Level: 0
    Overall activity: 38.0%
    Achievements:
    200+ Posts Achievement!First 1000 Experience Points400+ Posts Achievement365 Days+ Registered Achievement!Got three Friends
    Join Date
    Oct 2010
    Location
    Central California, USA
    Posts
    12,092
    Points
    61,950
    Level
    100
    Thanks
    2,215
    Thanked 5,447x 3,561 Posts

    Default

    Got the telescope up to O.W.L. today. Got a little tour from the owner/proprietor. Pleasant and smart guy from my impression. The place is not fancy/sharp looking, but he seems to have everything in good repair and functional and so for me he's hitting the sweet spot! (I like it when the emphasis is on function far more than on form).

    He's grinding a number of mirrors at this time. One of them is at his maximum capacity of 36 inches. His coating device/oven/whatever will apparently handle up to 22 inches so I'm not sure where the 36 incher is going to get its coating.

    He also has very significant machining ability/capacity. Including CNC functionality. I don't think he is making telescope mounts, though.

    I liked the guy, I liked his shop, and he says the thing will likely be ready for me to pick up on Wednesday or Thursday - which is pretty good turn-around, IMHO.

    Oh, and he says that the mirror issues I've got is, indeed, flaking and that it was due to poor cleaning/prep. There is a bit of a "swirl" pattern to the flaking and he says that is typical for problems as the mirror is being prepped/cleaned for coating. I'm not sure who, but I think it was someone on this forum who said that Celestron had some quality control issues at around the time this scope was likely made and this would just tend to confirm that.

    Oh, and I'm not entirely sure, but I think that this was likely the PowerStar-4 configuration/package. Doesn't really matter all that much. The Ultima-8 would have been preferable 'cuz I think they had a bunch of handles attached (and I think there were more power options. But then, I can probably find some good handles somewhere and bolt them on anyway if I really think I need them.

    Anyway, a special thanks to Joe since I think he got me to a link with a good outfit to work with. I guess my opinion might be dramatically different after I get the scope back and both learn how to use and to evaluate it - but I'm pretty confident I'll be satisfied.

  9. #17
    Tombstone17's Avatar
    Tombstone17 is offline HYPER GIANT
    Points: 18,068, Level: 92
    Level completed: 92%, Points required for next Level: 32
    Overall activity: 0%
    Achievements:
    10 Days registered200+ Posts Achievement!First 1000 Experience Points365 Days+ Registered Achievement!Got three Friends
    Join Date
    Oct 2009
    Location
    So. Cal. near Disneyland
    Posts
    2,938
    Points
    18,068
    Level
    92
    Thanks
    1,843
    Thanked 526x 471 Posts

    Default

    I think you will be happy in the long run. The shop sounded really cool, I love to meet people like that and make friends. Good luck with your New/old scope!!
    Enjoy the Black cause they can't take it back............
    To view links or images in signatures your post count must be 5 or greater. You currently have 0 signatures.
    Stoney
    Meade LX90-8" ACF, Meade DS 2090 AT, Cannon450 Rebel, US Navy made 10x50"
    <a href=http://cleardarksky.com/c/AnaheimCAkey.html>

    To view links or images in signatures your post count must be 5 or greater. You currently have 0 signatures.

  10. The Following User Says Thank You to Tombstone17 For This Useful Post:

    OleCuss (11-29-2010)

  11. #18
    ferkijel's Avatar
    ferkijel is offline Bright Giants
    Points: 3,239, Level: 37
    Level completed: 26%, Points required for next Level: 111
    Overall activity: 0%
    Achievements:
    200+ Posts Achievement!First 1000 Experience Points365 Days+ Registered Achievement!400+ Posts Achievement5 Threads Achievement!
    Join Date
    Oct 2010
    Location
    Switzerland
    Posts
    373
    Points
    3,239
    Level
    37
    Thanks
    17
    Thanked 140x 82 Posts

    Default

    I would use their full service, ESPECIALLY if they let me stick around and watch them work.
    Zhumell Z12 Deluxe 12" Dobsonian
    Celestron Astromaster 130 EQ
    A whole bunch of EP both 1.25" and 2"

  12. The Following 2 Users Say Thank You to ferkijel For This Useful Post:

    OleCuss (11-29-2010),Tombstone17 (11-29-2010)

  13. #19
    OleCuss's Avatar
    OleCuss is offline Curmudgeon
    Points: 61,950, Level: 100
    Level completed: 0%, Points required for next Level: 0
    Overall activity: 38.0%
    Achievements:
    200+ Posts Achievement!First 1000 Experience Points400+ Posts Achievement365 Days+ Registered Achievement!Got three Friends
    Join Date
    Oct 2010
    Location
    Central California, USA
    Posts
    12,092
    Points
    61,950
    Level
    100
    Thanks
    2,215
    Thanked 5,447x 3,561 Posts

    Default

    Quote Originally Posted by ferkijel View Post
    I would use their full service, ESPECIALLY if they let me stick around and watch them work.
    I did ask for the Silver Service and the semi-enhanced coating (he said the durability is about the same as the regular aluminum - and the reflectivity is better).

    I'd bet he'd let me watch - but I just can't be there so it isn't an option. . .

 

 
Page 2 of 2 FirstFirst 12

Similar Threads

  1. dns issues
    By ozzmozizz in forum Feedback Forum
    Replies: 30
    Last Post: 08-08-2009, 07:19 PM
  2. More important issues
    By oriel36 in forum Amateur Astronomy Forum
    Replies: 0
    Last Post: 08-24-2006, 11:01 AM
  3. Astrostack issues...
    By Xavier in forum UK Astronomy Forum
    Replies: 2
    Last Post: 06-12-2004, 09:11 PM

Tags for this Thread

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 12:26 PM.