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

What does this mean (on mirror edge)?

  • Please log in to reply
12 replies to this topic

#1 lphilpot

lphilpot

    Apollo

  • *****
  • topic starter
  • Posts: 1166
  • Joined: 15 Oct 2005
  • Loc: Central Lousiana, USA

Posted 11 December 2016 - 07:32 PM

This is the mirror in my 14.5" TeleKit, but it's not the original scope for the mirror. It was from a Sky Designs scope in the early '90s (I was the fourth owner at least). I've been told "D. J. Arthur" is Danny Arthur from Fort Worth Texas, which makes sense, as Sky Designs was located between Fort Worth and Dallas, IIRC. 65.5 in. is indeed the focal length.

 

But does anyone have any idea what "SD194" means?

 

Also, I've seen another 14.5" Sky Designs mirror posted for sale and the seller said it was Pyrex (that ad also mentions Danny). Not that it matters (to me), but is there any way to tell?

 

I'd ask Danny himself but I have no idea how to find him. :)

 

mirror_edge.jpg

 

Thanks.



#2 coopman

coopman

    Fly Me to the Moon

  • *****
  • Posts: 5359
  • Joined: 23 Apr 2006
  • Loc: South Louisiana

Posted 11 December 2016 - 07:35 PM

Sky Designs mirror no. 194?
  • dave brock, polaraligned and Pinbout like this

#3 junomike

junomike

    Hubble

  • *****
  • Moderators
  • Posts: 15825
  • Joined: 07 Sep 2009
  • Loc: Ontario

Posted 11 December 2016 - 08:51 PM

I see it as SD\94, so Sky Design 1994?

 

Mike


  • Jon Isaacs likes this

#4 lphilpot

lphilpot

    Apollo

  • *****
  • topic starter
  • Posts: 1166
  • Joined: 15 Oct 2005
  • Loc: Central Lousiana, USA

Posted 11 December 2016 - 09:09 PM

1994 is too late, I think. If memory serves, that scope was bought new (original owner) in maybe '90 to '92 at the latest I think. I, the scope's buyer and another guy were all going to the Texas Star Party together in a rented Dodge Caravan, leaving from various points in Louisiana. We picked up the scope en route, getting to Colleyville (TX) around 11:45 PM if I recall. Bob Coombs was there waiting for us, obviously. :)  The owner upgraded to an Obsession 25 in 1995, so I doubt he did that after only one year. But a plausible idea, nonetheless.

 

coopman may be right - It could be a serial number. I bought a Coulter 10" f/5.6 mirror around the same time and it had a 'comparator number' on it, according to Jim (?Braginton?). It was something like "-44", which was aparently a result of someone measuring an f/4.5 mirror thinking it was f/5.6 (hence the artificially large offset). The first mirror took 9 months; I got an f/5.51 replacement in a week. I also learned (the hard way) to not cut truss tubes until AFTER the focal length was verified...  :angry:

 

I'm wondering if that's what this number is: Some kind of quantifier? "SD" == "sagittal depth"? Or maybe just "seems decent".   :grin:

 

I have no complaints about the mirror - I've been observing through it (in one scope or another) for the past 12 years.

 

Thanks.



#5 Pinbout

Pinbout

    ISS

  • *****
  • Posts: 22168
  • Joined: 22 Feb 2010
  • Loc: Montclair, NJ

Posted 11 December 2016 - 09:53 PM

It probably means -  sky design #194 mirror.


Edited by Pinbout, 11 December 2016 - 09:53 PM.


#6 darthur1589

darthur1589

    Lift Off

  • -----
  • Posts: 4
  • Joined: 05 Oct 2015

Posted 12 December 2016 - 12:45 PM

Hi Len,

I am Danny Arthur.  A friend let me know about your post and so I am responding.  SD194 is the number of the mirror.  The numbering system started at some number and went forward from there.  SD stands for Sky Designs.  This mirror was made in February of 1992 and I must have really liked it because I noted in my records  Butefull!!  I'm glad you are enjoying the views it gives you. 

 

I'm very glad I had the opportunity to learn and work at Sky Designs.

Danny Arthur

 

 


  • Jon Isaacs, dave brock, Pinbout and 1 other like this

#7 lphilpot

lphilpot

    Apollo

  • *****
  • topic starter
  • Posts: 1166
  • Joined: 15 Oct 2005
  • Loc: Central Lousiana, USA

Posted 12 December 2016 - 07:18 PM

Thanks, Danny!

 

Barbara Wilson clued me into you possibly being "D.J. Arthur" when I mentioned it to her several years ago at TSP.

 

I actually had the original Sky Designs "VPT" scope for about a year or so. But by the time I acquired it, it had been somewhat 'ridden hard and put up wet', apparently. It wasn't in very great shape any more. I transplanted the optics into a TeleKit, which is very substantial: Strong as a herd of oxen and about as heavy! I turn 58 next month and I'm getting to where I'd like something a little easier to manage in and out of vehicles... but I hate to give up any aperture, particularly with a beautiful mirror. :waytogo:  I'm trying to figure out my best option now.

 

Thanks again for the response.

 

P.S. - Another friend of mine in the early '90s had an 18" Sky Designs scope. That was a substantial critter!



#8 darthur1589

darthur1589

    Lift Off

  • -----
  • Posts: 4
  • Joined: 05 Oct 2015

Posted 12 December 2016 - 11:01 PM

Please send my best wishes to Barbara if you have a chance.  I'd love to chat with her sometime.

 

Also, have you considered Dob Stuff(if memory serves me correctly).  I bet he could make you a kit that would lighten up

your load when it comes time to move your scope.  I'm so happy you like your mirror.  That means a whole bunch to me.

 

Thanks,

Danny Arthur


  • Jon Isaacs likes this

#9 Jon Isaacs

Jon Isaacs

    ISS

  • *****
  • Posts: 75475
  • Joined: 16 Jun 2004
  • Loc: San Diego and Boulevard, CA

Posted 12 December 2016 - 11:13 PM

Please send my best wishes to Barbara if you have a chance.  I'd love to chat with her sometime.

 

Also, have you considered Dob Stuff(if memory serves me correctly).  I bet he could make you a kit that would lighten up

your load when it comes time to move your scope.  I'm so happy you like your mirror.  That means a whole bunch to me.

 

Thanks,

Danny Arthur

 

Danny:

 

I just want to say hello and :welcome: to CloudyNights. 

 

This is quite a remarkable story, a tribute to the strength of the community. 

 

Jon Isaacs


  • darthur1589 likes this

#10 lphilpot

lphilpot

    Apollo

  • *****
  • topic starter
  • Posts: 1166
  • Joined: 15 Oct 2005
  • Loc: Central Lousiana, USA

Posted 12 December 2016 - 11:33 PM

Please send my best wishes to Barbara if you have a chance.  I'd love to chat with her sometime.

 

Also, have you considered Dob Stuff(if memory serves me correctly).  I bet he could make you a kit that would lighten up

your load when it comes time to move your scope.  I'm so happy you like your mirror.  That means a whole bunch to me.

 

Thanks,

Danny Arthur

I see Barbara and the rest of TSP gang somewhat 'in passing' each year, but I'll definitely try to remember and let her know. I've done more than a few of Larry Mitchell's TSP advanced observing lists (and John Wagoner's lists, as well) through your mirror. Great views.

 

Interesting you mention Dennis (Steele at DobSTUFF). I've been trading emails with him on that very topic. At this point, I'm still very much in "thinking it over" mode, but with the OTA (alone) of my TeleKit weighing in at about 90 lbs, plus rocker box, etc., it's something I want to address at some point. The (nominally) 14.5" mirror box is actually big enough to hold a 17.5" (maybe 18") mirror, if I were to remove the internal batteries. Big, strong and built to last. But h-e-a-v-y ...   :)   TKs are beautiful and very well made, but it's getting a little bit over the top as time goes on... and my car has gotten smaller.

 

I don't know what happened to the 18" SD I mentioned (guy named Charlie Humphrey). He bought and sold astro equipment quite a bit and he passed away a few years ago. But I think he may have already traded it for something else before then.

 

Thanks again.



#11 darthur1589

darthur1589

    Lift Off

  • -----
  • Posts: 4
  • Joined: 05 Oct 2015

Posted 12 December 2016 - 11:53 PM

Thanks Jon.  I'm glad my friend Jim Craft let me know about this thread on Cloudy Nights.  I'll be  checking in regularly

to see what's happening.

Danny Arthur


  • Jon Isaacs likes this

#12 Mike I. Jones

Mike I. Jones

    Skylab

  • *****
  • Posts: 4345
  • Joined: 02 Jul 2006
  • Loc: Fort Worth TX

Posted 13 December 2016 - 12:47 AM

Bout time you got on here, McDanny!  :grin:

Jonesey



#13 darthur1589

darthur1589

    Lift Off

  • -----
  • Posts: 4
  • Joined: 05 Oct 2015

Posted 14 December 2016 - 02:09 AM

Yes indeed, Jonesey.  I am way late in arriving.  I have just completed a bunch of maintenance on my house and now get

to return to mirror work.  Oh boy!

 

Talk to you soon,

Danny




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