Celestron Nexstar 130 & William Optics Binoviewer

[Ace Rimmer]

Hi All, Just thought I'd try a Binoviewer with my Nexstar 130, I bought a William Optics Bino but can't seem to get focus on anything with it, it came with 2 20mm lenses and a 1.6x Barlow but no matter how I try and set it I can't get it to focus on anything with or without the Barlow, any advice or anything I can do or is it another waste of money to be put on eBay :-)

[brantuk]

When you use a binoviewer you effectively lengthen the light path considerably. Remember the scope is designed to focus somewhere within the throw of the focuser tube - and with these you will be quite a way outside that range. With an sct there is a lot more focus range and binoviewers will come to focus somewhere within that usually. Some refractors can focus using them - others can't or may require combinations of extenders and/or barlow.

How they work with newtonians though I don't know - someone who knows will answer that for you - but just thought I'd help you think about it a bit more when buying accessories - a little research or a few questions here first - might have been useful to you.

[sunshine185]

Does the 1.25" eyepiece holder unscrew? If so you could try that, its what I do on the dob, and can achieve focus with the 1.6x corrector.

[sunshine185]

Like this

[JamesM]

I found a similar question here on this forum dating back to April 25th 2010 (...It's not that I have a good memory - just that I did a quick google search for you :grin: ) and you can read it here.

Hope that helps

James