Budget binocular pair

[neilmack]

Looking at a pair of 20mm eyepieces for a binoviewer. The candidates are the Vixen NPL or the Starbase Ortho

 Does anyone have experience of either, or have had opportunity to compare the two?

 

thanks,  Neil

 

 

 

 

 

[Knighty2112]

I had one 6mm starbase ortho then when I got my binoviewers I got another to match too to use in the binoviewers. Sadly one of them never lined in the EP socket correctly in the binoviewers no matter how carefully I inserted it in, so no good in my binoviewers at least as this made them not line up correctly. I think the issue is they have a shorter part that locates into any 1.25’ socket. Any EP with a longer socket part should work OK. The length of the socket part on the Starbase is 20mm, whereas on the Starguider EP and most other EP’s I own this is aprrox 25mm.

 

[Louis D]

First off, what f-ratio is the scope you're going to be using it in?  Second, will you be using a Barlow to boost the power and/or reach focus?  It makes a difference in the required quality of the eyepiece for wide fields of view.  The NPL being a Plossl should be fine at f/6 and above.  I don't know if they're worth about twice the money of the Astro Essentials or Revelation 20mm Plossls.  Has anyone compared them to see if the lens polish, coatings, and stray light control of the NPLs are that much better than budget Plossls?

I use a 2x Barlow nosepiece operating at 3x in my binoviewers, so I have an effective f/18 focal ratio or longer in my scopes.  As such, a pair of SVBONY 68° Ultra Wide Angle 20mm eyepieces work great for me.  They just about max out the unvignetted field in my BVs.  I wouldn't recommend them for scopes below f/10 natively, though.

I wrote up my thoughts on the SVBONY below:

 

[neilmack]

Knighty, Louis

thank you both. I haven't bought the binoviewer yet, so some more window shopping to be done .....