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Telrad alternative suggestion for dobsonian

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#1 m1618

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Posted 16 August 2013 - 12:20 AM

I do not own a Telrad or a dob yet. After looking through a Telrad at a star party, I was convinced!

My concern: the mounting base installation.

Most likely when I purchase the dob I'll be transporting it in a van. Will probably roll around and stay in the heat. I'd prefer something more like a shoe/base finder mount but of some reflex type. Anyone having issues with the mounting base with Telrads?

Please suggest some alternatives you use as finders for a dob. thanks in advance!

#2 derangedhermit

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Posted 16 August 2013 - 01:24 AM

If you plan on the Dob rolling around in the back of a van, it won't last very long. Actually, the last thing to survive might be the Telrad - they are durable.

The Telrad is the best finder to start with, if the Dob is 8" or larger.

#3 David Knisely

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Posted 16 August 2013 - 02:32 AM

I do not own a Telrad or a dob yet. After looking through a Telrad at a star party, I was convinced!

My concern: the mounting base installation.

Most likely when I purchase the dob I'll be transporting it in a van. Will probably roll around and stay in the heat. I'd prefer something more like a shoe/base finder mount but of some reflex type. Anyone having issues with the mounting base with Telrads?

Please suggest some alternatives you use as finders for a dob. thanks in advance!


Nope, there is never much of a problem with the Telrad's base. My Telrad's base has been both bolted to my 10 inch Newtonian's tube as well as just stuck on the upper cage of my 14 inch truss-tube Dobsonian using the included adhesive tape, and the base has stayed put pretty darn well over the years in each case. I always remove the Telrad from the base when I am transporting the telescope, as that is just a question of releasing two nylon set screws and taking the Telrad off of its base, but the base is not bulky and fits fairly flush to the tube. I also have 8x50 straight through and 9x50 RACI finderscopes on both telescopes in addition to my Telrad, although much of the time, the Telrad is enough to find many objects. If you want something not quite as bulky for a smaller scope, the Rigel Quickfinder is OK, although it is a bit on the fragile side and its removal from the base not quite as easy:

CN REPORTS: Telrad Vs. Rigel Quickfinder

Here is how the Telrad (with its orange dew shield) and my 9x50 RACI finderscope fit on the front of my XX14i 14 inch f/4.6 Newtonian:

Attached Files



#4 Jon Isaacs

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Posted 16 August 2013 - 04:03 AM

Most likely when I purchase the dob I'll be transporting it in a van. Will probably roll around and stay in the heat. I'd prefer something more like a shoe/base finder mount but of some reflex type. Anyone having issues with the mounting base with Telrads?



I have 5 scopes with Telrads. I can only second what Lee and David have said. If your Dob is free to roll around in the back of your van, the Telrad base will be the least of your concerns. It has a low profile and it is robust. Other things like the focuser, the focuser shaft, these are going to get quickly damaged. When transporting a Dob, it should be protected and secure. Wrap it in an old blanket or sleeping bag, position it and block it in so it can't roll around.

In terms of secure finder brackets, I have never had a problem with a Telrad bracket. Dovetail brackets are more problematic, they have a much smaller footprint and often shift.

Jon

#5 RAKing

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Posted 16 August 2013 - 07:52 AM

Go ahead and add me to the list above!

The Telrad base will last longer than your focuser if you allow your OTA to roll around in the back of a van. :shocked:

I wrap a blanket around mine and block it with some old pillows.

Cheers,

Ron

#6 csrlice12

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Posted 16 August 2013 - 08:45 AM

Mine sets in the back seat and is seat-belted in. I just leave the Telrad and finderscope on it normally, but if I travel a good distance or over rough terrain (highly unlikely), I'd probably remove them as well. If you scope is allowed to roll around by itself, it'll at a minimum require recollimation, possibly hammering out the dents, and worst case....that tinkling sound WAS your mirror.....

#7 cliff mygatt

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Posted 16 August 2013 - 08:50 AM

I have my Telrad mounted on a finder scope foot from Scope Stuff here, it was just easier to get the large finder scope and Telrad mounted side by side. Here is the link to the telrad finder foot system: http://www.scopestuff.com/ss_telo.htm

#8 m1618

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Posted 16 August 2013 - 10:02 AM

I love this forum! Great advice and feedback.
Didn't realize at first that there's an option to bolt them on not just the adhesive.

One other thing I really liked about the Telrad approach was not hitting my eyeglasses on a magnified finder.

The only other concern now is remembering to turn it off when not in use.

Thanks again everyone!

#9 tag1260

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Posted 16 August 2013 - 10:10 AM

I've found mine left on after weeks at a time and still have the original batteries. Man, why can't they make everything use juice like this thing!!!

#10 Jeff Morgan

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Posted 16 August 2013 - 10:14 AM

The only other concern now is remembering to turn it off when not in use.


Even leaving it on has not been much of a problem for me - sometimes I have inadvertently left mine on for a month at time. The power draw at low settings is minimal, although that being said the wise astronomer always has a pack of spare batteries in the tool box.

BTW, when I have had to remove a Telrad base (move to a better location, different scope, etc.) it has been quite a task to get the old base off due to the length (and surface area) of the double-stick surface. Naptha works well against the adhesive and has minimal effect on finishes (although you would of course want to test that discretely).

When archaeologists dig up our civilization millions of years from now, Telrads will probably be the only devices intact and functioning.

#11 csrlice12

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Posted 16 August 2013 - 10:19 AM

Well, there will still probably also be eyepiece cups intact...functioning is another story altogether.....

#12 cliff mygatt

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Posted 16 August 2013 - 10:27 AM

By the way, you might want to purchase the Telrad pulser kit and install it, very nice upgrade. Available here. Good Luck!

#13 n1wvet

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Posted 16 August 2013 - 10:32 PM

You may also want to look at a flip mirror addition to the Telrad. Makes it even more useful at weird viewing angles. Is dew a concern where you live? If so the Telrad will dew up first. You'll need to look at adding some warming resistors or dew shields. All said, the telrad still works well.

#14 petrus45

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Posted 16 August 2013 - 11:08 PM

I love this forum! Great advice and feedback.
Didn't realize at first that there's an option to bolt them on not just the adhesive.

One other thing I really liked about the Telrad approach was not hitting my eyeglasses on a magnified finder.

The only other concern now is remembering to turn it off when not in use.

Thanks again everyone!


Also try gluing flexible fridge magnets to the bottom of the telrad base. Then you can remove it and snap it back on at will. Works great for me.

#15 starbux

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Posted 17 August 2013 - 12:43 PM

As others have said, the Telrad base should not be an issue.

But have you considered wrapping your dob tube in a blanket or two? It will minimize rolling and denting as well as provide insulation from the heat. I always wrap my dobs in a blanket when transporting. Just my 2 cents.

#16 dan777

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Posted 17 August 2013 - 07:50 PM

Please suggest some alternatives you use as finders for a dob.


A green laser pointer.
After I bought the GLP I quit using the Telrad, so I sold it.

#17 Jeff Morgan

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Posted 17 August 2013 - 09:10 PM

Please suggest some alternatives you use as finders for a dob.


A green laser pointer.
After I bought the GLP I quit using the Telrad, so I sold it.


That's what I'm doing on the new scope. I just need two short bursts to get ServoCAT alignment and it's off to the races. I could even remove the GLP from that point, but it's location doesn't really affect balance at all.

If this works out long-term I'll sell one or both of my Telrads.

#18 CeleNoptic

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Posted 18 August 2013 - 10:06 PM

Anyone having issues with the mounting base with Telrads?

Please suggest some alternatives you use as finders for a dob. thanks in advance!

1) No. 2) No serious alternatives. I still have the Rigel and I don't like it.

dan777
A green laser pointer.
After I bought the GLP I quit using the Telrad, so I sold it.

.
I had tried the GLP on my Dob and found it didn't make finding objects much easier. So, I went the opposite direction and bought the Telrad instead. But YMMV.

#19 Shawn H

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Posted 19 August 2013 - 08:00 AM

Lasers & red dot pointers work fine, but I prefer the bullseye rings of the Telrad! ;)

#20 SKYGZR

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Posted 20 August 2013 - 04:39 PM

I prefer the Rigel..smaller foot print, it's just to get one close ayway..

#21 csa/montana

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Posted 20 August 2013 - 04:46 PM

it's just to get one close ayway..



I find that using the Telrad with charts with the Telrad circles, I get right on the target, unless there are few stars around the target in order to place the circle; then I can use my RACI.

#22 Wmacky

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Posted 20 August 2013 - 06:33 PM

I think it's time for a Telrad update. A little less plastic would work for me.

#23 gravitino

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Posted 20 August 2013 - 10:13 PM

Here is how the Telrad (with its orange dew shield) and my 9x50 RACI finderscope fit on the front of my XX14i 14 inch f/4.6 Newtonian:


David,
Is that the Astrosystems Telrad dew shield? Where did you get an *orange* one?!!

Clear skies,
-- Shane

#24 Jon Isaacs

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Posted 20 August 2013 - 10:29 PM

it's just to get one close ayway..



I find that using the Telrad with charts with the Telrad circles, I get right on the target, unless there are few stars around the target in order to place the circle; then I can use my RACI.


:waytogo:

If the skies are dark, then most often, a Telrad is all that is necessary.

If there is insufficient room for the Telrad, in my experience, a Rigel can be used but with the increased parallax error and without the 4 degree ring, I did not find it as effective as the Telrad.

Jon

#25 m1618

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Posted 20 August 2013 - 10:38 PM

So Telrad it is. Mine came in the mail today. Impressive. I do think that the magnet strip idea is great. They better have strong ones at the hardware store.

Yes I will be sure to wrap my scope with a sleeping bag.
Telrad does need a makeover. The components inside are very radioshack. A lot of excess plastic. Wondering what the purpose of the big battery compartment was. I can hide my car keys in there during star parties I guess. But what a great invention. I wish Telrad continued success!

Thank you all for your advice and setting me straight about going with the "industry standard."






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