Bought a Vixen SSW 14mm

[MortonH]

Steve Massey of MyAstroShop brought some of these to Astrofest. I tried the 14mm in a 20" SDM as well as my own scope and was so impressed I bought one. Another attendee bought the 7mm and the 14mm. We both agreed they were very Nagler-like but with more comfort than the T6's. The eye lens on the 14mm is large and the adjustable eye cup works really well. I'm a happy camper!

[ab1963 (Andrew)]

what is the colour neutrality like in comparison to the 13 nagler t6 Morton

[Camelopardalis (Dunk)]

Oh you bad bad boy you know you've doomed Sydney to more cloud now...

[MortonH]

Originally Posted by ab1963

what is the colour neutrality like in comparison to the 13 nagler t6 Morton

Damn. I was too busy enjoying the view to think about that. When I get the chance I'll compare it to my DeLite, which is neutral.

[AstroJunk (Jonathan)]

Yup, that 14mm star tested very well indeed! Neutral tone and good across the field of view at f5 (ie coma exactly where it was supposed to be). Very good at that price point and a country mile better than a Pentax XW 14mm we star tested that night.

[ausastronomer (John Bambury)]

Originally Posted by AstroJunk

a country mile better than a Pentax XW 14mm we star tested that night.

Hi Jonathan,

I know from that comment that you were not using a paracorr.

The 14mm and 20mm Pentax XW's need to be used with a paracorr in any newtonian faster than about F6. When used with a paracorr they perform superbly. Without one they are pretty average. The 17mm and 22mm Nagler T4's are the same. Ordinary without a paracorr, exceptional with a paracorr.

Cheers
John B

[Don Pensack]

My field experience with the SSWs are that they are fairly sharp, have good contrast, and are nice and bright (good polish and transmission).
This was in a 12.5" f/5 dob WITH Paracorr.
They all however, and it's worse the longer the focal length, have significant spherical aberration of the exit pupil, on a par with the TeleVue Nagler Type 1s back in the '80s.
What that means is that holding the eye exactly in place is required to prevent kidney bean shadows in the field, and eye placement is significantly more finicky than many other eyepieces.
Adjusting the eyecup perfectly is a requirement to avoid this.
Many people may feel that this is justified by the optical characteristics.

I don't know how they are priced in Oz, but here in the States they are more expensive than the TeleVue Nagler Type 6 eyepieces, which have no SAEP and are not particularly sensitive to eye placement.

[MortonH]

Originally Posted by Don Pensack

My field experience with the SSWs are that they are fairly sharp, have good contrast, and are nice and bright (good polish and transmission).
This was in a 12.5" f/5 dob WITH Paracorr.
They all however, and it's worse the longer the focal length, have significant spherical aberration of the exit pupil, on a par with the TeleVue Nagler Type 1s back in the '80s.
What that means is that holding the eye exactly in place is required to prevent kidney bean shadows in the field, and eye placement is significantly more finicky than many other eyepieces.
Adjusting the eyecup perfectly is a requirement to avoid this.
Many people may feel that this is justified by the optical characteristics.

I don't know how they are priced in Oz, but here in the States they are more expensive than the TeleVue Nagler Type 6 eyepieces, which have no SAEP and are not particularly sensitive to eye placement.

Hi Don,

I remember reading your impressions of the SSW's a while back. It put me off them a bit (they weren't available in Oz at the time and the US price being higher than the Naglers was a deal-breaker). I almost certainly wouldn't have bought one without trying it first. The interesting thing is that I found no issue whatsoever with eye placement - it was very comfortable and easy to use (I don't wear glasses).

The regular price for the SSW's in Oz is $410, compared to $479 for a Nagler T6. There was a discount on the price at the star party, and I also saved on the shipping cost by picking it up there, so I got a good deal.

[Don Pensack]

Sounds good. If you saved money and got an eyepiece with which you are quite compatible, everything lines up.
I wonder if Vixen will release more 83° focal lengths eventually. They might not be the same configuration as the SSWs, but there is plenty of room for at least 3 longer focal lengths.

[MortonH]

Tonight I had a quick session at home - the first one since Astrofest. Using my SV66ED I tried the SSW to see if there was any issue with eye placement. Looking at the moon I could detect 'something' if I moved my eye in a certain way but nothing that I would call a blackout. I then lowered the eye cup to its lowest position and found some blackouts occurring, not horribly so but noticeable. Adjusting the eyecup to its former position made the blackouts disappear.

I noticed that the eye cup in its most comfortable position fits very nicely around my eye socket and cheek. If I relaxed and just enjoyed the view there were no eye placement issues. Only when I deliberately moved my eye around in an 'unnatural' way could I start to see the 'something' again.

Comparing this experience to the 13mm T6 I sold a few months ago is interesting. The Nagler had no blackout issues but I was never completely comfortable with the eye cup (for one thing I felt it was too short). The SSW's adjustable eye cup is very comfortable and helps to provide an immersive view.

As an added bonus, the red colour of the eyepiece matches my red SV66ED!