Really got to give my WO binoviewer a thrash tonight, and Im over the moon! - I cant go back to Cyclops vision now.
I was pretty worried because a few people in cloudy nights have been pretty critical of the WO, but I cant really see what is wrong with it or what you will get by going with a much more expensive model. Perhaps I got lucky
I'm with you on binoviewing Tim, I was converted a few years ago and recently upgraded to a pair of WO's and I think they perform very well.
I have an 150mm f6.5 refractor that I made, with binoviewing in mind, so that I can reach focus without the OCS, this arrangement with the 20mm wide angles gives me an 80' fov which is fine for most bright dso's and several pairs of ortho's for lunar and planetary observing, though the f 6.5 starts to struggle at mags over 200X.
I have an 150mm f6.5 refractor that I made, with binoviewing in mind, so that I can reach focus without the OCS, this arrangement with the 20mm wide angles gives me an 80' fov which is fine for most bright dso's
The whole idea of the barlow lens amplifier is to increase the f ratio so that you can get the light of a faster mirror or lens through the long narrow light path in the binoviewer. Using a stock binoviewer at F6.5 you may be loosing a third to a half of your 6" lens through vignetting at the mouth of the binoviewer.
I have a pair of WO binoviewers as well which I absolutely love for lunar and planetary views.
I find the views too dim though with my 10" dob on dso's so I stick with lunar/planets.
That's my experience too; I find I observe for longer periods with bino's because it's easier on the eyes (assuming good collimation) and so much fun, but I need every bit of light I can get with most DSO's.
Can be difficult at first but once you get it all set up for your eyes there's nothing better!
The WO BV's are super value and work very well.
Nice to have some Denk's or Earthwin BV but there expensive and on the wish list
Yes, the only issue I have noticed is that you need LOTS of eye relief - I purchased a pair of 9mm TMB's, and while it works, you really cant move you head much at all.
Don't want to sidetrack this topic, but thanks for your knowledgable input Satchmo, I was obviously working off the theoretical TFOV for the system and completely forgetting what I was actually seeing at the eyepiece(s). Maybe something to do with not actually remembering because it's been so long since we've had any clear sky down this way. The lightpath through the BV is certainly vignetting the light cone from the objective lens, from memory the field stops in the eyepiece holders is about 18mm. Can't wait to test in the field to measure what I'm actually seeing, maybe only 50' arc !
