Quote:
Originally Posted by stonewalled
Ok thanks guys for the advice.
I'll probably go with the Barlow (which explains the Vixen) as the next acquisition but I think I'd like to see how these guys go first.
Paul
|
If you buy a barlow buy a good one. That doesn't necessarily mean expensive.
The good expensive ones are the Televue Powermate, Televue 2X, Televue 1.8X, Dakin 2.4X, TMB, Zeiss, Takahashi and Astrophysics.
The good cheap ones are the Orion Ultrascopic 2X and the Orion Deluxe 2X.
Some barlows to avoid are:-
1) Klee 2.8X. Because of its very short focal length and its narrow clear aperture it vignettes with medium to longer focal length eyepieces. Moreso with some designs than others. With long focal length plossls it has major problems. With short focal length eyepieces it is an excellent barlow.
2) Another to avoid is the Meade #140 (sorry Dannat). I believe there can be some variation in quality with these, possible due to poor QC and some show a definate darkening of the target due to reduced light transmission.
With the other cheap barlows you get what you pay for.
Also keep in mind that if there are no mechanical requirements for a short barlow, a long barlow will always outperform a short barlow.
Cheers,
John B