Meopta s2 82 hd + astro eyepieces (1 Viewer)

[tenex]

I now have the Meopta astro adapter. Seems very nice, but do note that it has a substantial safety stop at the bottom that limits the eyepiece shaft to around 25~26mm. So nothing longer than that (TV zoom!), and no filters. Might be awkward with non-removable 2" skirts like Morpheus? Haven't tried it out yet, arctic weather here.

 

[tenex]

I can report that the astro adapter works well (in daytime also) with a 5mm DeLite, giving a comfortable 88x with nearly 1mm exit pupil (I didn't want to go any smaller). The DeLite isn't parfocal with the Meopta zoom, does focus to infinity but not quite as close. It has good eye relief adjustment and gives me no problems in use. It will complement the 30-60x zoom well.

 

[DRodrigues]

I can report that the astro adapter works well (in daytime also) with a 5mm DeLite, giving a comfortable 88x with nearly 1mm exit pupil (I didn't want to go any smaller). The DeLite isn't parfocal with the Meopta zoom, does focus to infinity but not quite as close. It has good eye relief adjustment and gives me no problems in use. It will complement the 30-60x zoom well.

You are loosing AFOV compared to the 30-60x zoom. I would go for a >=70º ep.
A 4.5mm ep would work also well with the Meopta, enlarging the ep choice at the 5-4.5mm range. See test of 5mm astro eps

 

[tenex]

Thanks, DR. I had thought of 4.5mm and/or wider field but the choices weren't as appealing... in the end I'm about to try one I'd overlooked, Nikon 5mm NAV-SW, with 72° but not too large/heavy. I do expect to like it better.

The eyepieces i have for my 82 meopta is baader morpheus 12.5 mm, 17.5 mm, 14 mm with 76 deg fov. I also has apm 13 mm and 5 mm with 100 deg fov. All of these works great on the scope with no vignetting.

I just noticed this. Having previously suggested that fieldstops over ~20mm will vignette on the S2, you report that the 17.5 Morpheus (with 23.6mm fs) doesn't. So the limit varies with particulars of eyepiece design? I'd like to know what's worth trying!

 

[tenex]

I now have the 17.5mm and 5mm NAVs; both work well with the adapter, and I like their 72° AFOV. The 5mm at 88x is great for observing across large lakes. The 17.5 has a 22mm field stop but doesn't seem to vignette, as Racuuna says the 16mm Nagler (with its 82°) does. For what it's worth the S2's sealing window looks about 22mm, though it's recessed and hard to measure accurately.

 

[Tringa45]

I now have the 17.5mm and 5mm NAVs; both work well with the adapter, and I like their 72° AFOV. The 5mm at 88x is great for observing across large lakes. The 17.5 has a 22mm field stop but doesn't seem to vignette, as Racuuna says the 16mm Nagler (with its 82°) does. For what it's worth the S2's sealing window looks about 22mm, though it's recessed and hard to measure accurately.

I measured the sealing windows on my scopes by progressively cutting down a strip of paper until it matched their diameters. If you choose longer focal length/wide-field eyepieces with field stops smaller than the sealing window, vignetting should not be a problem.

John

 

[tenex]

I measured the sealing windows on my scopes by progressively cutting down a strip of paper until it matched their diameters. If you choose longer focal length/wide-field eyepieces with field stops smaller than the sealing window, vignetting should not be a problem.

That's exactly how I measured the window as 22mm, to within 1mm. In any case my 17.5 NAV has a 22mm fs and doesn't vignette; Racuuna's 17.5 Morpheus actually has 23.6, but he says it still doesn't, while his Nagler does. The 17.5 NAV is lovely and very easy to swap with the 5mm, more stable than switching the astro adapter with the Meopta zoom in the bayonet mount.