Telrad

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Jessi
Posts: 94
Joined: Wed Sep 16, 2020 1:23 am
Real Name: jessica palmer
Location: Saint Paul

Telrad

Post by Jessi »

I have a 13" Dobsonian and a Telrad. Any tips on lining it up. Right now the telrad is just sitting on the table next to the scope.
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Sureshks
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Joined: Fri Aug 29, 2014 10:43 pm
Real Name: Suresh Sreenivasan
Location: Hopkins, MN

Re: Telrad

Post by Sureshks »

Hi Jessi,

If I understand your question properly, you are trying to line up the telrad with your main scope?

The easiest way to do it at night is to use the Moon. It's a big bright object that you can easily find in your telescope without the finder. Once it's centered in the eyepiece you can adjust the three knobs on the front of the telrad to maneuver the red telrad circles so that the Moon is also centered.

If there's no Moon available, just take the scope out during the day and find a far away tree branch, roof or window and do the same.

I hope this helps!

Suresh
Suresh Sreenivasan
B-SIG/FB/Metcalf Comm

Refr: AP 130mm GTX/SW 120mm/Borg 4"/Unitron 150 4"/Jason 2.25”
Dobs: ATM 16"/Orion 12”
Newts: Cave 8" RFT/Criterion RV6/Astroscan 4"/Orion 3.6" TCT
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SCTs: Celestron 9.25"/8”/B&L Criterion 4”
Maks: SW 7"/Quantum 4"/Meade 3.5” ETX
Cass: Vixen 8” VISAC/Simmons 4.5"
RC: MallinCam 10"
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Jessi
Posts: 94
Joined: Wed Sep 16, 2020 1:23 am
Real Name: jessica palmer
Location: Saint Paul

Re: Telrad

Post by Jessi »

Thanks! I'll give that a try. But first I need to actually attach the base to the scope.
Jessi
Posts: 94
Joined: Wed Sep 16, 2020 1:23 am
Real Name: jessica palmer
Location: Saint Paul

Re: Telrad

Post by Jessi »

The adhesive is kind of intimidating...I feel like there's no room for error.
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SEmert
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Joined: Mon May 31, 2004 2:48 pm
Real Name: Steve Emert
Location: White Bear Lake, MN

Re: Telrad

Post by SEmert »

Don't be intimidated. It's easy, and even if you get it totally crooked you can get it back off by sawing through the foam tape with a piece of dental floss, then rubbing the rest of it off with your thumb. More tape is available at hardware stores or Menards and elsewhere.

But to get it straight, what I do is tape a piece of string along the length of the optical tube assembly all the way from front to back, right next to where you want to mount the Telrad. That way you can use it as a guide in lining it up. When you've got it lined up, just press it down and it's mounted.

When aligning the Telrad, just like any finder scope, be sure to first sight on something distant with the scope then adjust the knobs on the Telrad to sight it in on what the scope is seeing. Very difficult the other way around!
Steve Emert
MAS Membership Coordinator
12.5" f/4.7 Obsession Clone Homemade Truss Dob, sometimes equipped with Celestron StarSense Explorer app
Celestron C8 SCT OTA on AVX GEQ mount
Astro-Tech AT72 ED Refractor OTA usually on Explore Scientific Twilight 1mount or tripod with Benro geared head
Celestron 5" SCT OTA on Synta AZ-4 or Explore Scientific Twilight 1 Alt-Az Mount, usually equipped with StarSense Explorer app
Orion 150mm Mak OTA and Orion EQ-G computerized mount
Jessi
Posts: 94
Joined: Wed Sep 16, 2020 1:23 am
Real Name: jessica palmer
Location: Saint Paul

Re: Telrad

Post by Jessi »

Thank you for replying! I will definitely try the dental floss trick. I feel a little more confident about installing it now.
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