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[NoobWatcher]

This thread is for those who have any interest in making thier own custom Telescope. I am in the very begining phases of the design and Manufacture of a 12.5" Dob. The current concept calls for all the bells and whistles from the start. For those just tuning into this project is projected to run thru the summer. I am very familiar with manufacturing but have never constructed a Telescope. I will ask for input so please feel free to offer constructive critisizm. The project will run int the following order:

1. Research design and written bill of materials developement.

2. Purchase or reservation of extreme long lead items (done)

3. MFG and purchase components per BoM.

4. Assembly

5. Testing and corrections if required.

I am proceeding with step 1 and expect it to run for a several months. I will be off reading and reserching all the required components to construct the project. In the end I will post my BOM ( bill of materials ) with component cost projections. So if you have any good item recommendations please post them with the the component # and manufacturer.

"And So It Begins"

Best regards
Scott

[NoobWatcher]

Well my first read of "The Dobsonian Telescope" By David Kriege / Richard Berry is complete. I actually made it 300 pages in before I started skimming. I dont claim to know much about telescopes, I do know quite a bit about manufacture. The book is a must have if you are to ever consider constructing your own Dob (in my opinion ). The book is written with enough high tech for the math people out there and common sense talk for the average person. It will be my bible as I continue the project. The book makes it tempting to build really big! I maintained my cool and I am staying with the 12.5 in order to keep the size down for more ease of mobility.

I am now truely ready to begin design. I have couple questions which welcome opinions. These issues affect overall design so I must solidify them.

1. Focal length: with a 12.5" reflector I am currently thinking of f/5. Would I be giving up alot by going to f/4?

2. Auto tracking: I have had very limited success in finding a Alt/Az tracking package. Any knoun good systems out there?

I am off to the start the snow blower . Hope you all are surviving the weekend of snow! Take Care.

[stargazer]

Scott,

Here is some people to contact for parts.

Starlight Instruments - Focuser www.astrofieds.com/docs/feathertouch.htm
(This is the focuser I have. After the trip you can stop by the house and I will show you how it is.)

Orion 9x50 finder scope, and the Orion Epic ED2 eyepieces. The best that I have found. www.telescope.com

Kendrick for dew heaters. trust me you will want them.
you'll have to google for their web site. we have them for the finderscope and the telrad, the eyepieces. and a fan for the primary.


As for the focal length I would talk that over with Dan. Mine is a F/4.85. Tell Dan what you want to do with it and he will help you set it up for that. Remeber think about what you want to do with it in 3 years not now. I will dig up who we went with for the heated secondary and let you know who we went with.

Scott I will call you when I get home to see how things are going and to set it up with you to come overand see he scope.

As for the Auto Tracking I have the Tech 2000, 600 to 1
motors. We paid $600 for the system. Tracks well if the scope is level. Great for photography.

Well guys just 11 more days till I fly out of this cold and into some nice weather. I have a planned observing system set up. Will finish two more certs and work on two for C.L.A.S.S. work on two others cert. That just puts me three away from the Masters Observing Award. I am really looking foward to this trip.

Becky

P.S. Right now the sky is Crystal Clear here.(10:43 P.M.) Stars galore, Im not going to do any observing cause Im letting my eye heal before the trip. I injured my observing eye last week and it needs to heal before the trip.

[Chicago Astronomer - Astro Joe]

Excellent on your beginning the research process!

I read just yesterday a review in Astronomy magazine on a 8" - f/4 reflector scope. The reviewer stated that it had excellent wide FOV, but optically - near the edges of the mirror - the stars developed a "coma" or smeared effect. Near the center the images were as sharp as can be. So maybe the f/5 is the better selection.

Maybe you could look into something else than a base unit to mount your future 12.5" in. A fork mount would be so cool...and different. Make sure you incorporate a rotatable collar for the focuser/spider assembly to obtain the best comfortable viewing position.

Anticipating your next thoughts.

[stargazer]

Scott,

Here is some info for you.

what you would lose:
F/4 Larger diameter light cutoff. More money, Forgives factor in optics, need Perfect collumination for optics.

F/5 This is the best deal for photography for the 12.5". Easier to columinize. I would go with this one with this being your first scope.

Now for the secondary I would go with the 4" heated and 4 vein spider. I have never seen a difference with the curved spider vs. the stright. I have the stright. That is your choice.

I hope this helps you with your choice for focal length.

Becky

[NoobWatcher]

Thx guys, I will stay with the f/5. It will still be able to fit in my camper.
I have been making progress in locating many purchase Items. I will eventually compile a list for your thoughts. Becky where did you purchase that tech 2000 hardware? It continues to elude me

Best Regards
Scott

[stargazer]

Scott

If you google tech 2000 or roboscope it should come up. We found them on the net. I dont reccommend the goto program as it wont work on anything other then a 98 puter but the drives I would say yes to. If I find the info I will let you know.

Becky