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View Full Version here: : Does anyone know of a good 5x Barlow


lineout
20-02-2007, 01:52 PM
Hey everyone,

Just wondering if anyone could recommend a good (actually v.good) 5x Barlow? Price isn't really a consideration.

Cheers in advance.

ving
20-02-2007, 01:58 PM
televue powermate.... nuff said ;)
its what the pros here use.

lineout
20-02-2007, 02:08 PM
I was considering the Meade series 5000. How does it compare?

iceman
20-02-2007, 02:34 PM
Do the Meade make a 5x barlow? I've only ever seen the Powermate as a 5x barlow.

It's the best. About $290.

janoskiss
20-02-2007, 02:39 PM
If "price isn't really a consideration", just get the Powermate. I have not used the Meade product in this instance, but with every other meade EP or barlow I compare to similar TV product, I consistently find TV to be clearly superior in every way.

I assume you want a 5x barlow for imaging. It has very limited use for visual observing.

matt
20-02-2007, 02:58 PM
5x Televue Powermate is the go.

If money is no object, buy two!:lol::lol:

Yes..they are that good.

lineout
20-02-2007, 03:05 PM
Yeah I need it for imaging.

I'll look at the TV.

Thanks for the help.:)

merlin8r
20-02-2007, 03:42 PM
Meade make a 5X Telextender, as well as a 2X and 3X, and a 2" 2X.

Clear skies,
Shane

lineout
20-02-2007, 03:53 PM
Sorry all these names are confusing. Is that the same as a barlow?

davidpretorius
20-02-2007, 04:25 PM
i can honestly say my 5x powermate is awesome and the best $290 i have spent. The beuaty is that if you add a 100mm extension tube, then you get 7.7x!

matt
20-02-2007, 04:37 PM
Dave

Do you know how to calculate the extra magnification based on the length of extension tube used?

I've got a 50mm extension tube.

Was wondering what that would give me when combined with my 3x TV barlow or 4x Powermate?

But would also like to calculate what other length extension tubes would give me when used with a variety of barlows/powermates with the 9.25???

Anyone else with the answer please feel free to chime in:)

davidpretorius
20-02-2007, 05:10 PM
http://televue.com/engine/page.asp?ID=42

1/2 way down the page for the graph

davo

matt
20-02-2007, 05:14 PM
Yeah. Seen that before.

Not exactly precise.

Want to be able to calculate mag from which barlow i'm using with what length ext tube etc

davidpretorius
20-02-2007, 05:26 PM
cool, not sure of the maths

Dennis
20-02-2007, 07:20 PM
What 'scope are you planning to use the x5 PowerMate or Barlow on? I have a x5 PowerMate and the seeing conditions only become favourable between 6 and 10 nights per annum for my Vixen 4" F9 refractor and even less for my Celestron C9.25 F10 SCT.

Cheers

Dennis

janoskiss
21-02-2007, 12:07 AM
Matt, have a look at this page for info on using barrel extensions with barlows: http://www.atmsite.org/contrib/Carlin/barlow/

matt
21-02-2007, 07:54 AM
Thanks Steve:thumbsup:

merlin8r
21-02-2007, 09:07 AM
A telextender performs the same job as a barlow, but has more elements in it. Plus the build quality is better. I doubt it would perform as well as a Nagler though!

Clear skies,
Shane

lineout
21-02-2007, 10:01 AM
I'll be using it on an 8 inch LX-90 GPS.

I'm now torn between the Meade tele-extender and the Powermate.

janoskiss
21-02-2007, 10:33 AM
Apples and oranges, microwaves and TVs. Nagler being an eyepiece would make a pretty useless barlow. :poke:

I have been told that the tele-extenders work on the same principle as the powermates.

merlin8r
21-02-2007, 11:02 AM
The Powerview is not made by Nagler?

janoskiss
21-02-2007, 11:26 AM
TeleVue is the company. Nagler is a type of eyepiece made/sold by TeleVue. You must be thinking of the TeleVue Powermate. :)

merlin8r
21-02-2007, 11:28 AM
Oh I see. I didn't explain myself well! Al Nagler invented the Nagler, and started the Televue company. I meant the man, not the eyepiece. D'oh!

Dennis
21-02-2007, 02:25 PM
Your 8 Meade is an F10 system, so using a x5 PowerMate would make it an F50 system. I rarely see any images taken at F50. I think that most high resolution Lunar and Planetary imagers seem to operate between F20 and F40, with the optimum range around F25 to F35.

The only time I have used the x5 PowerMate on my C9.25 F10 system is when I was imaging the Trapezium in Orion using the SBIG ST7.

Cheers

Dennis

netwolf
25-02-2007, 09:23 PM
If you want a cheaper alternative barlow range is made by Paul Rinni, you can usully find them on Ebay or Surplushed. Search for Rinni on ebay.


Regards
Fahim

Phil
26-02-2007, 09:05 PM
Televue powermate is the go if money is not a problem