Click here if you are having trouble logging into the forums
Privacy Policy |
Please read our Terms
of Service | Signup and
Troubleshooting FAQ | Problems? PM a Red or a Green Gu.... uh, User
Albie
Post Laureate
Reged: 02/22/05
Posts: 3521
Loc: Alberta,Canada
|
|
Hello everybody.
I am considering selling my 1.25" Celestron Ultima 2x barlow and getting either a Meade 2x telextender 2" or a 2" Televue 2x.I would like to get the Televue to keep things green  but am worried that it will cause too much er with my 26T5.I find the 26T5 perfect the way it is and don't want to disturb it.The Meade I think acts like a powermate and won't disturb the eyerelief,hopefully.Also I am wondering if the magnification with either barlow is 2x or slightly over or under like my Ultima which is said to be roughly 2.2-2.25x rather than it's stated 2x power.
Any suggestions,input or first hand experience??
--------------------
Skywatcher 10" f/4.7 Dob with Moonlight CR1
Televue 2x barlow and 5T6,7T6,9T6,16T5 and 26T5 Televue Naglers.
SkyMaster 15x70,Regal LX 8x42 and Noble 10x28
|
FirstSight
Carpal Tunnel
Reged: 12/26/05
Posts: 2517
Loc: Raleigh, NC
|
|
Albie:
Get the 2" 2x TV Powermate. It works seamlessly on all TV Naglers (and Ethos) without altering eye relief or degrading the view. The only visible effect inserting a Powermate into the optical train is that it raises the height of the eyepiece above the optical tube. It has no effect on the view whatsoever - no noticeable dimunition of light or degradation of the sharpness of the view, no vignetting, no lessening of TFOV or AFOV, etc.
And precisely to your point - NO effect on eye relief whatsoever. See this article at the Televue website specifically about Powermates v. Barlows (including comments about eye relief):
http://www.televue.com/engine/page.asp?ID=42
--------------------
Chris M., aka "First Sight"
Orion XT12i Dob with Moonlite CR-2 focuser
WO Megrez 90 refractor on UniStar Light mount
Nikon 10x50 Binoculars
Edited by FirstSight (09/18/08 01:45 PM)
|
jimmoscheck
Pooh-Bah
Reged: 01/08/07
Posts: 1059
Loc: Under the SE Michigan lightdom...
|
|
I concur with Chris. The powermate is the way to go, although I don't usually use it with the 26T5 as it is fairly large. I have a 12T4 for that magnification and do like using both the 12 and 17T4 with the powermate for higher magnifications.
If I didn't have the 12T4 I would use the powermate with the 26T5.
--------------------
Jim Moscheck
14.5" f4.3 home built Kriege stlye truss
Stevens primary
"A mind is like a parachute. It doesnt work if it's not open." - Frank Zappa
|
Tom D.
Carpal Tunnel
Reged: 11/29/04
Posts: 1609
Loc: Boca Raton, FL
|
|
Albie:
The 26T5 (27 oz) + the 2" 2X Powermate (22 oz) = a shade over 3 lbs...alot of weight. For about the same price as the Powermate, you can get a 13T6 (10 oz).
Tom
--------------------
Orion ShortTube 80 (f/5.0)
Stellarvue SV105 (TMB/LZOS f/6.2)
DiscMounts DM-4/Sky Commander XP4
"Aerodynamics are for people who cannot build engines"......Enzo Ferrari
|
Albie
Post Laureate
Reged: 02/22/05
Posts: 3521
Loc: Alberta,Canada
|
|
Quote:
Albie:
The 26T5 (27 oz) + the 2" 2X Powermate (22 oz) = a shade over 3 lbs...alot of weight. For about the same price as the Powermate, you can get a 13T6 (10 oz).
Tom
Good point something I forgot to consider.If I were to consider a focal length between the 9 and the 16 it would have to be an 11T6,better fit with my scope imo.I had a 13T6 and a 17T4 and sold them both in favor of a 16T5 and an 11T6.I never did get the 11 and I'm still not sure if I need it.I figured that a 2" barlow or telextender/powermate would allow me to barlow all my ep's if desired or needed.The weight thing is a killer for sure.I didn't like having to adjust my focuser to except the weight of the 26T5,it makes focusing with the smaller ep's not quite as buttery smooth as it can be with the Moonlight.So having to readjust for 3lbs would be worse for sure although I'm sure it can be done.Dob balance not really much of an issue with the tension adjust handle.
I'll withdraw my questions until the next time I get cravings to buy something,anything 
Thanks for the suggestions.
--------------------
Skywatcher 10" f/4.7 Dob with Moonlight CR1
Televue 2x barlow and 5T6,7T6,9T6,16T5 and 26T5 Televue Naglers.
SkyMaster 15x70,Regal LX 8x42 and Noble 10x28
|
|
4 registered and 6 anonymous users are browsing this forum.
Moderator: Greg K., Jason B, csa/montana
Print Thread
|
Forum Permissions
You cannot start new topics
You cannot reply to topics
HTML is disabled
UBBCode is enabled
|
Thread views: 142
|
|
|
|
|
|
|
Previous
Index
Next
Threaded
Edit
Reply
Quote
[Re: 