Jump to content

  •  

CNers have asked about a donation box for Cloudy Nights over the years, so here you go. Donation is not required by any means, so please enjoy your stay.

Photo

Celestron C90 Registry

  • Please log in to reply
161 replies to this topic

#151 dannyleo

dannyleo

    Lift Off

  • -----
  • Posts: 3
  • Joined: 24 Dec 2020

Posted 26 December 2020 - 08:50 PM

THANKS ANM!  Appreciate your quick help.



#152 RSX11M+

RSX11M+

    Vostok 1

  • -----
  • Posts: 164
  • Joined: 27 Dec 2019

Posted 10 January 2021 - 03:39 AM

Thank you for your submission.
 
dannyleo - I have seen C90s with baffle issues repaired, some are chronicled in CN forums. The disconnected secondary baffle in your images (that's what it appears to be) can be re-attached. You need to get advice on the type of glue. Be sure to avoid Cyanoacrylate (aka: "crazy glue")  as they will give off vapors while curing which damage optics and mirrors.

I agree with ANM that the most likely cause of the damage to the primary baffle would be solar induced, though I've not personally seen that before.

 

I cannot imagine getting help from Celestron on this, but it's always worth a call to get advice.

 

These are not too difficult to disassemble, clean and put together, so don't be discouraged. 

 

The new Registry with these additions is offered in JPG and PDF.
 



#153 SkiWhiz72

SkiWhiz72

    Lift Off

  • *****
  • Posts: 2
  • Joined: 22 Jan 2020
  • Loc: NW Ohio

Posted 28 January 2021 - 08:48 PM

Hello I have two C 90

 

Orange spotter #910866 optic #347 gold band 5x24 finder

 

Orange spotter #97357 optic#4424 gold band



#154 dannyleo

dannyleo

    Lift Off

  • -----
  • Posts: 3
  • Joined: 24 Dec 2020

Posted 01 February 2021 - 10:19 AM

Thanks SkiWhiz72.  SpaceNut59 already answered and I bought his.  Appreciate it.



#155 Ps191

Ps191

    Mariner 2

  • *****
  • Posts: 222
  • Joined: 17 Jun 2009
  • Loc: E. OR

Posted 01 February 2021 - 09:41 PM

Can anyone help me understand what can be learned from this c90 registry?
I've looked over the data and there seems to be no rhyme or reason to its order. What does it tell us and how do we interpret its data?

Thanks,

#156 RSX11M+

RSX11M+

    Vostok 1

  • -----
  • Posts: 164
  • Joined: 27 Dec 2019

Posted 02 February 2021 - 12:09 AM

Can anyone help me understand what can be learned from this c90 registry?
I've looked over the data and there seems to be no rhyme or reason to its order. What does it tell us and how do we interpret its data?

Thanks,


Well, let's see... We can't know what patterns might emerge until we've collected the data, but judging by a more complete Registry like that for the C8, we learned a lot.

The most common thing we are asked is "When was my particular scope manufactured?", and the only data an owner can provide is the Serial Number. With a C8, the SN can now be used to determine the date of manufacture to a very precise degree. With the C90s, we only have a general idea at this point.

We eventually expect to be able to make a good guess as to when production features changed. When orange tubes were dropped in favor of Black. When the F5.6 versions were made.

There doesn't seem to be much correspondence among optics numbers as yet, but it may be possible to glean something from these as well, once enough data is amassed.

Those of us with F11 and F5.6 models have noticed some mechanical differences in the corrector mounts and in baffle tube parameters. Understanding these differences may eventually lead to a deeper understanding of optical artifacts of different vintages and how to cure them and what performance characteristics usually suffer.

Collected data often helps those who would like to work on, restore or repair their scopes gain more pre-knowledge on what they are about to undertake.

 

Beyond that - it's just plain fun. cool.gif


Edited by RSX11M+, 02 February 2021 - 12:19 AM.

  • Kasmos and Stevegeo like this

#157 dannyleo

dannyleo

    Lift Off

  • -----
  • Posts: 3
  • Joined: 24 Dec 2020

Posted 02 February 2021 - 10:14 AM

Wow.  I didn't know they made an f5.6!  That sure seems like quite an improvement over my f11.  Correct me if I'm wrong, but that's twice as fast and therefore I can shoot at twice the shutter speed for shooting range work, or get double the exposure for night work.  Isn't that a win-win all around?  



#158 RSX11M+

RSX11M+

    Vostok 1

  • -----
  • Posts: 164
  • Joined: 27 Dec 2019

Posted 02 February 2021 - 11:30 AM

dannyleo - Yes, the F5.6 is faster and has a wider FOV. For photography, it has a mixed bag of aberrations, so it's not the best telephoto lens for most applications. (the smaller your image circle the better) However with a controlled situation, it's benefits can be exploited.

 

I myself became interested after seeing C90 F5.6 registry entries, and managed to get one in decent condition. So the registry served me - as one example. Hopefully others will find the C90, C5 and C8 registry information beneficial for their purposes.

 

It's difficult to know how "information" such as the registries provide will be useful. I had to think in order to answer Ps191's inquiry,  because what's possible changes as information accumulates.  Each member has their own desires and may see implications we don't recognize - we hope they will share.

 

One aspect that's come up, with the C8 in particular, is the desire to morph one of the datums into an ownership attribution. This hasn't been fully adopted, but there is value to members that might want to know "provenance" of a particular instrument's collectibility or in case of theft. The registry isn't yet well suited to these uses but the idea has come up and been accommodated to some degree. 

 

Understanding of the C8's evolution has provided so much detail that we can offer a particular scope's production date range based solely on characteristics. (without Serial Number) -Something that would have been impossible with commonly available information.

 

However, the moderators don't like us to stray too far from a threads's topic, so delving deeply into a particular aspect of a model or it's performance imperils that rule. Should such an interchange be desirable it can take place in one of the other suitable forums. I will entertain such here, if it is candidate for addition to a Registry's information, or just in answer to a quick question.

 

You can always shoot me a private message if in doubt as to a subject's suitability.



#159 RSX11M+

RSX11M+

    Vostok 1

  • -----
  • Posts: 164
  • Joined: 27 Dec 2019

Posted 25 February 2021 - 03:03 AM

Thank you SkiWhiz72 for your two submissions since January 10.

"Orange spotter #97357 optic#4424 gold band" - you called this a "Spotter" configuration but didn't mention a finder. Was there a finder at some point that is now missing? Just curious, we usually count on photos for these details.

 

 

"Orange spotter #910866 optic #347 gold band 5x24 finder" -  This is an optics number we might have expected from SN 900xxx, but for SN 910xxx  should be well above optics #2000. Could you please re-verify these numbers?

 

We have entered your scopes under the data as you provided, and will correct the entry immediately if you indicate we should.

 

Thank you 

 

 

The new Registry with these additions is offered in JPG and PDF.
 



#160 SkiWhiz72

SkiWhiz72

    Lift Off

  • *****
  • Posts: 2
  • Joined: 22 Jan 2020
  • Loc: NW Ohio

Posted 25 February 2021 - 09:15 PM

Hello,I double checked my scopes. C90 97357 came without a finder,I mounted one without modifying the scope. I do not know its previous history. C90 910866 lens number reads 347, I know this seems out of order but I do not know the history of this scope either. I do not have a good way to send pictures. Thanks Steve



#161 RSX11M+

RSX11M+

    Vostok 1

  • -----
  • Posts: 164
  • Joined: 27 Dec 2019

Posted 26 February 2021 - 04:15 AM

Hello,I double checked my scopes. C90 97357 came without a finder,I mounted one without modifying the scope. I do not know its previous history. C90 910866 lens number reads 347, I know this seems out of order but I do not know the history of this scope either. I do not have a good way to send pictures. Thanks Steve

Thank you very much for going to the trouble to re-check those numbers. While they are curious, we already entered them as you originally indicated.

 

We are often left to wonder how such things evolved, perhaps a natural consequence as their age more and more surpasses that of their owners. If only they could talk.



#162 Borodog

Borodog

    Apollo

  • -----
  • Posts: 1,328
  • Joined: 26 Oct 2020

Posted Yesterday, 01:04 PM

This is the C90 given to me by my father-in-law. Looking at the registry, I believe it is the 6th oldest C90 on the list and the 3rd oldest astro version thereof. The serial number is 9550. There is no number on the optics. Orange tube, black focus ring, gold band, 5x24 finder, all original eyepieces and 2.5X Barlow, case, manual, working worm gear drive, original wedge and tripod, mounting bolts. The only things that are missing are some covers and caps, which I have kludged with film canisters and caps, and the power cord. Luckily the power cord from my '85 Celestron-Byers Word Gear Drive C8 fits. The finder bracket is not straight enough to align to the main scope; hence the shim, which I need to replace with a more attractive version.

 

 

 

 

Attached Thumbnails

  • C90_9550.jpg



CNers have asked about a donation box for Cloudy Nights over the years, so here you go. Donation is not required by any means, so please enjoy your stay.


Recent Topics






Cloudy Nights LLC
Cloudy Nights Sponsor: Astronomics