180 replies to this topic

[highfnum]

can someone explain this?

 

"I have remounted the mirror on bubble wrap"

 

i dont get it

[CHASLX200]

can someone explain this?

 

"I have remounted the mirror on bubble wrap"

 

i dont get it

I guess it is better than the crude support the stock cell gave the blank. Them thin mirrors deform easy.

[CHASLX200]

I miss every one of my Odyssey's I've ever owned especially my 17.5 I have had

more wow's and smiles from the Coulter Odyssey than any other telescope.

Here's a old photo I just finished cleaning my 17.5 mirror in the kitchen sink, look at the size of it !

Yes that is a dishwasher below the mirror and yes that thought did cross my mind !

Robert

 

post-50896-14073911044859_thumb.jpg

Looks good. Don't drop it on a toe and clam it up.

[apfever]

Looks good. Don't drop it on a toe and clam it up.

clam the mirror or clam the toe?

 

Here's a copy from another string: The big red scope thing that matches the big red other thing has been getting some RKE performance. Discussion of resolution is redundant. I have nebulosity off the field of view with wisp twist recognized in a third dimension. By early before sunrise, thermal help had the star blobs down to realistic 1/2 size blobs. At any rate, the blobs were distincly reduced. The Trap in Orion was far more contrasty, clear, and deep.  The red Coulter is, and was meant to be, a regression in the face of the recent flak thrown before it. It has been called a de-evolution of equipment with entries detailing the horrors required to essentially turn a Ford Pinto into a Pierce Arrow. If you have to do that to be happy then START WITH A DIFFERENT SCOPE.

[highfnum]

on with  bubble wrap again

so it means mirror sits on a piece of bubble wrap that is cut to proper size?

and then held down with clips?

 

and the advantage is ?

[apfever]

It will work pretty good. So will artificial turf that is fairly uniform on a halfway decent flat back.

Two things about artificial turf support, it can go flat like a slow leak in a tire and it's not good ventilation full face plant. 

Bigger mirrors make more sense for multiple lawns. 

 

Bubble wrap is close if pad size. I wouldn't want 3 single pillows. 

Edited by apfever, 18 November 2021 - 10:02 AM.

[EJN]

Yes, and then as now such change was marked by devolution rather than evolution when it came to the Coulter dob.

 

Time for some photo phun.

 

Cycles of time

 

[clamchip]

can someone explain this?

 

"I have remounted the mirror on bubble wrap"

 

i dont get it

I haven't done it myself but from my reading you use 1 inch cell bubble wrap to support the

mirror over it's entire back.

I suppose to hold the mirror in place over this cushion of air I would use a sling to support the

mirror's edge from 3 O'clock all the way past 6 O'clock to 9 O'clock with a safety clip at 12:00.

 

Robert

[clamchip]

Here's the stock mirror cell for a blue tube Odyssey.

Nine point flotation cell with a sling.

This works really well and I love the "tailgate" so you can open up for quick equalization.

You should not transport the telescope with the mirror in the scope, keep it in a mirror 

box.

Coulter index's the mirror and the cell with felt dots so you can remove/install the mirror

every time without much or any collimation trim.

Robert 

 

[clamchip]

I should mention the tailgate is John Dobson's idea. In fact the Coulter Odyssey is John Dobson

and is why I love the Odyssey. It has the simplicity and personality of John's telescopes.

The Odyssey traces a direct line back to the early years of Mr Dobson's telescopes.

I just wish I could have been there. Where was I? I was here but I think the whole dob movement

was California in the early days.

From more of my reading I think I remember reading somewhere the tailgate served two purposes.

Transport and while figuring the figure you can open the tailgate and scrub off a millionth with your

thumb here and there, close it up and immediately see the results in the eyepiece.

 

Robert

Edited by clamchip, 18 November 2021 - 11:20 AM.

[EJN]

The Odyssey traces a direct line back to the early years of Mr Dobson's telescopes.
I just wish I could have been there. Where was I? I was here but I think the whole dob movement
was California in the early days.

I was aware of the Dob movement through coverage of RTMC in Sky & Telescope. In 1976, when I was 18, I was met by this at the Grand Canyon:

 

 

 

You can see all the elements of the Coulter design were based on this.

[clamchip]

Here's a piece on John Dobson in the national parks:

http://www.sidewalka...tionalparks.pdf

 

Robert

[Kasmos]

Here's the stock mirror cell for a blue tube Odyssey.

Nine point flotation cell with a sling.

This works really well and I love the "tailgate" so you can open up for quick equalization.

You should not transport the telescope with the mirror in the scope, keep it in a mirror 

box.

Coulter index's the mirror and the cell with felt dots so you can remove/install the mirror

every time without much or any collimation trim.

Robert 

 

post-50896-1407391106874_thumb.jpg

What is the stapled down material and it's purpose? It also looks a little puffy?

[EJN]

What is the stapled down material and it's purpose? It also looks a little puffy?

 

From what I recall, it's vinyl material which covers the collimation screws under the triangles, and the triangles are attached to it so they are free to float but not rotate. It's probably the simplest and cheapest method of making a 9-point flotation cell that still works.

[CHASLX200]

I was aware of the Dob movement through coverage of RTMC in Sky & Telescope. In 1976, when I was 18, I was met by this at the Grand Canyon:

 

 

 

You can see all the elements of the Coulter design were based on this.

Slow Newts are the only way to go.

[DreamWeaver]

What is the stapled down material and it's purpose? It also looks a little puffy?

It's hide from the now endangered Nauga.  

[Kasmos]

It's hide from the now endangered Nauga.  

Don't laugh, there really was a Nauga

 

http://www.voicesofe...yl-monster.html

 

[Terra Nova]

I never had one, not a dob of any kind really tho I’ve had a number of Newtons including several I’ve built. I hated them (Dobsonians) for years but gradually came to like them. I could say that they grew on me. Especially the red Coulters. They have a certain rustic charm. A je ne sais quoi, if you will.

[Jehujones]

[clamchip]

I recently traded my brown tube Odyssey 8 to a friend and it is covered with genuine

Nauga from the factory.

I kinda liked thinking of it as the Western Ranch Odyssey.

Robert

 

Edited by clamchip, 18 November 2021 - 11:59 PM.

[Terra Nova]

image.JPG

Notice at the bottom of the ad above, that Coulter Optical was located in Idyllwild, California. Idyllwild is a lovely little montane village in the San Jacinto Mountains, above Palm Springs in Riverside County. I always loved driving the very scenic Palms to Pines Highway, but you could also take the historic tram up the mountainside to Idyllwild from Palm Springs. Did you know that Idyllwild has the distinction of having a very popular mayor who happens to be a dog?

 

https://nypost.com/2...wn-for-8-years/

Edited by Terra Nova, 19 November 2021 - 10:34 AM.

[clamchip]

I would like to visit Idyllwild someday.

One of my favorite places is Paradise on Mt Rainier.

Pine trees remind me of Stumpy.

I miss you so much my lil' friend.

Robert

 

Edited by clamchip, 19 November 2021 - 10:52 AM.

[Jon Isaacs]

Good pics showing the devolution. I had never thought of it that way before.

 

But the marketplace often mimics the same Darwinian elements of life. The new creatures (the Dobs) didn't require much food (low cost), so they multiplied in great numbers and consumed most of the food (customers money) leaving little left for the previous creatures (the classics), who needed much food (expensive) to survive. The few that survived into the modern era include the adaptable (jack of all trades) creature known as the C8 or those that found a unique ecological niche like the creature called the Questar.

 

It's true that Dob's were much cheaper than the old EQ mounted Newtonians but I think the ultimate success of the Dobsonian was because it was more practical, more usable. 

 

I owned both these 12.5 inch Newtonians for a number of years.. Both were purchased used, both were about $500.  One of them I still own. One of them has been all over the southwest, one of them never made more than 25 feet down the driveway.  The Dobsonian made easily transported large aperture telescopes possible. Today, a 12 inch fits nicely in many cars.. 

 

 

 

Regarding the Coulters:

 

It is my understanding that many were tested using a flawed test plate, much like the Hubble and that their mirrors were flawed for that reason.. Any thoughts?

 

I had a 13.1 inch blue tube briefly.  What a monster.. I had the 12.5 inch Discovery in the photo at the same time.  I think the 13.1 inch OTA weighed 85lbs, the Discovery OTA was around 50 lbs after I replaced the particle board mirror cell.

 

 

Jon

 

 

 

 

 

[lunardave]

Not fitting in my Bolt.

Nor mine for that matter!

[clamchip]

I found a few more pictures of my 17.5" blue tube.

Her name is Bluey and she lives in Chile now

I made a dolly with jack screws to level the scope.

Because of my unlevel driveway the telescope had motion problems, leveling the scope 

fixed this problem. I would use a scissor jack to level, screw down the jacks.

The large wheels sure were nice too. I could easily move the big girl.

The rear photo shows the 3 collimation screws and the screw in each upper corner are

for opening the tail gate.

Just look at the beautiful condition. Completely original paint etc.

Robert