Binoview EP's options

[callisto]

Just now, JeremyS said:

I haven’t Mark. I note they are quite short FL. Many ppl, including myself, find it more comfortable  to get high mags using longer FL eyepieces (which generally have better ER) with a Barlow (or GPC) in front of the binoviewer. 

Ahh, ok Jeremy thanks

I haven't used Binoviewers before 🤔

[Louis D]

54 minutes ago, callisto said:

Hi all,

Don't mean to hi jack the thread...has anyone used a pair of these in a Binoviewer? 

https://www.firstlightoptics.com/skywatcher-eyepieces/skywatcher-uwa-planetary-eyepieces.html

 

Mark

Merging high power eyepiece views can be problematic because they can expose any slight collimation issues in the binoviewer.  I do as Jeremy suggests above, use low power eyepieces with a Barlow element out front of the BV.  Since I end up operating at 3x or about f/18, just about any wide field eyepiece looks great.

[Deadlake]

45 minutes ago, JeremyS said:

with a Barlow (or GPC) in front of the binoviewer. 

If you can buy a GPC that is 😁

[JeremyS]

1 hour ago, Deadlake said:

If you can buy a GPC that is 😁

I bought a 1.7 x Baader GPC last week 👍

[Don Pensack]

2 hours ago, JeremyS said:

I haven’t Mark. I note they are quite short FL. Many ppl, including myself, find it more comfortable  to get high mags using longer FL eyepieces (which generally have better ER) with a Barlow (or GPC) in front of the binoviewer. 

In this case, all focal lengths have a long eye relief, so there is no disadvantage to the short focal lengths.

Note that almost all binoviewers have a magnifying nosepiece on the front end, so a 10mm eyepiece might be operating as a 5mm eyepiece in the binoviewers.

Hence, very short focal lengths might not be necessary.

Edited September 20, 2021 by Don Pensack

[Deadlake]

I've settled on the Takahashi 18.5 mm LE eyepieces, for the high power views would it be best to get the 15 mm APM UFF or go with the 12.5 mm LE's?

I'd use a GPC 2.6. I suspect the 12.5 mm LE's would be the max for most nights I could use due to seeing?