2,532 Brands 453 Categories All Departments

A question re: telescope as spotting scope

Need our opinion on a telescope Optics Planet has on sale, go ahead and ask! Post some hints and tips on various telescope brands and configuration.

A question re: telescope as spotting scope

Postby ljgold@charter.net on Fri Jan 23, 2009 9:33 am

I have a Televue Ranger with the 45* erect prism diagonal (which I think limits magnification to less than 100X). My ocular is the 17mm Plossl.

I use this telescope as a spotting scope on the target range. At 300 yards I cannot reliably see .30" holes punched through paper. I bought a 9mm Nagler, but it dims the target so much that it is less effective than the 17MM Plossl.

Does anyone have a recommendation?

Thank you.

Harley
ljgold@charter.net
 

Postby Jne_K on Fri Jan 23, 2009 9:55 am

Hi

First, if you are using a 45 degree erect image prism, dump it. 45 degreee erect image prisms are notorious for robbing you of much needed resolution. I used to own a Televue Pronto - much improved scope with a standard mirror diagonal. The Televue 1.25 diagonal will bring out the most in your Ranger. It will still give you upright images, though reversed right to left.

A 60mm aperture is always pushing it for that distance. You typically need to move up to a larger objective to get the kind of resolution you want. Switching to another eyepiece, especially if you are using a Nagler, is not the answer.

Keep in mind, that atmospheric conditions - turbulence, mirage, dust, humidity - are also a big factor at thses longer distances. It is the atmosphere, as much as the optics, that limits how much magnification you can use and it takes a very good day to even use 60x and almost never will you be able to use 100x. This can even change by the hour, so you will need to try your Ranger several times to get a good idea of what it can and cannot do.
Thanks for posting with us
Joanie K - Your personal optics expert

Forum: http://www.opticsplanet.com/msgboard
Blog: http://blog.opticsplanet.com/
Store: http://www.opticsplanet.com/

Phone: (800) 504-5897
Fax: (847) 919-3003
Jne_K
Site Admin
 
Posts: 7665
Joined: Wed Sep 24, 2003 3:09 pm

Postby Harley on Fri Jan 23, 2009 10:04 am

Thank you for your reply. A couple of points: 1. This is a 70MM, not 60MM objective; 2. I bought this scope from OpticsPlanet as their recommendation for my stated purpose.

Okay, what would you do in my situation? Spend the money for the diagonal ocular? Sell the scope and buy something better suited for targets?

If your advice is to replace the scope, do you have a recommendation?

Thanks.
Harley
 
Posts: 6
Joined: Fri Jan 23, 2009 9:24 am

Postby Jne_K on Fri Jan 23, 2009 10:14 am

Hi

Sorry, I meant 70. When did you buy this? The Ranger has been gone for sometime, now.

I would give the Ranger another couple tries to eliminate the atmosphere as a variable. I would also try to borrow a good diagonal, rather than buy one, to see if that will do the job. If you have a local astronomy club in the area, someone will probably lend you one, but even an average grade mirror diagonal will be an improvement.

My usual recommendation for 300 yard work is, as a minimum, the Bushnell Elite 20-60x80, but to be honest, I find it hard to believe that the Ranger could not do the job under the right conditions and with a good diagonal.
Thanks for posting with us
Joanie K - Your personal optics expert

Forum: http://www.opticsplanet.com/msgboard
Blog: http://blog.opticsplanet.com/
Store: http://www.opticsplanet.com/

Phone: (800) 504-5897
Fax: (847) 919-3003
Jne_K
Site Admin
 
Posts: 7665
Joined: Wed Sep 24, 2003 3:09 pm

Postby Harley on Fri Jan 23, 2009 11:37 am

I just looked, but can't locate my receipt; however, I do still have your Spring-Summer 1996 catalog, so I suppose that was the year I bought the Ranger.

Thanks for the idea of locating an astronomy group; but, for the sake of added options, if I decided to take a blind chance and order the correct diagonal, what brand, model number, source and price do I need to know?

Should I replace the supplied 17MM Plossl; if so, with what?

I appreciate all your help.

Harley
Harley
 
Posts: 6
Joined: Fri Jan 23, 2009 9:24 am

Postby Jne_K on Fri Jan 23, 2009 12:25 pm

Hi

Wasn't us, since we don't publish a catalog and were not around in 96, but glad to help, anyway.

You can certainly go all out with the Televue Diagonal 1250, but the Stellarvue D1031ED is also very good.
Thanks for posting with us
Joanie K - Your personal optics expert

Forum: http://www.opticsplanet.com/msgboard
Blog: http://blog.opticsplanet.com/
Store: http://www.opticsplanet.com/

Phone: (800) 504-5897
Fax: (847) 919-3003
Jne_K
Site Admin
 
Posts: 7665
Joined: Wed Sep 24, 2003 3:09 pm

Postby Harley on Fri Jan 23, 2009 12:45 pm

You're right, I took another look at that catalog......Eagle Optics.

You've given me a lot of homework to do; thank you.

Harley
Harley
 
Posts: 6
Joined: Fri Jan 23, 2009 9:24 am

Postby Jne_K on Fri Jan 23, 2009 12:55 pm

You are very welcome.

By the way, that's where I bought my old Televue Pronto. Great folks.
Thanks for posting with us
Joanie K - Your personal optics expert

Forum: http://www.opticsplanet.com/msgboard
Blog: http://blog.opticsplanet.com/
Store: http://www.opticsplanet.com/

Phone: (800) 504-5897
Fax: (847) 919-3003
Jne_K
Site Admin
 
Posts: 7665
Joined: Wed Sep 24, 2003 3:09 pm

Postby Harley on Fri Jan 23, 2009 12:59 pm

I just researched the Stellarvue D1031ED; it seems to have it all. I'm an impulse shopper, so you'll probably have my order today. :D

Should I increase the magnification, also, from my current 17mm Plossl?

Harley
Harley
 
Posts: 6
Joined: Fri Jan 23, 2009 9:24 am

Postby Jne_K on Fri Jan 23, 2009 1:04 pm

Hi

A shopper after my won heart.

Yes, but that's where your Nagler should work just fine. Remember, as magnification goes up, image brightness goes down with any eyepiece, not just your Nagler.
Thanks for posting with us
Joanie K - Your personal optics expert

Forum: http://www.opticsplanet.com/msgboard
Blog: http://blog.opticsplanet.com/
Store: http://www.opticsplanet.com/

Phone: (800) 504-5897
Fax: (847) 919-3003
Jne_K
Site Admin
 
Posts: 7665
Joined: Wed Sep 24, 2003 3:09 pm

Postby Harley on Fri Jan 23, 2009 1:06 pm

Done! I'm pretty excited about this.

Harley
Harley
 
Posts: 6
Joined: Fri Jan 23, 2009 9:24 am

Postby Jne_K on Fri Jan 23, 2009 1:14 pm

That's great, Harley

Enjoy!
Thanks for posting with us
Joanie K - Your personal optics expert

Forum: http://www.opticsplanet.com/msgboard
Blog: http://blog.opticsplanet.com/
Store: http://www.opticsplanet.com/

Phone: (800) 504-5897
Fax: (847) 919-3003
Jne_K
Site Admin
 
Posts: 7665
Joined: Wed Sep 24, 2003 3:09 pm

Postby Harley on Fri Jan 23, 2009 1:19 pm

I just ordered the diagonal and included an "atta-girl" for you.

Harley
Harley
 
Posts: 6
Joined: Fri Jan 23, 2009 9:24 am

Postby Jne_K on Fri Jan 23, 2009 1:21 pm

Thanks for the order, Harley. Been a pleasure.
Thanks for posting with us
Joanie K - Your personal optics expert

Forum: http://www.opticsplanet.com/msgboard
Blog: http://blog.opticsplanet.com/
Store: http://www.opticsplanet.com/

Phone: (800) 504-5897
Fax: (847) 919-3003
Jne_K
Site Admin
 
Posts: 7665
Joined: Wed Sep 24, 2003 3:09 pm