Vixen SLV 2.5mm Eyepiece

[cloudsweeper]

I went for this to get more magnification from my short-focus fracs - the Exp Sci ED80 Apo and the Bresser AR102S - instead of bothering with a Barlow.

It has an anti-roll profile and twist-up (clicks into three positions) eyeguard.  It is compact and lightweight – just 267g, including adaptor.

There is a Skywatcher “UWA” 2.5mm at 40% of the cost, with five elements, 58deg AFOV, and 16mm of eye relief, but the seven-element Vixen should I expect perform rather better, and gives a useful 20mm eye relief (specs wearer) no doubt at the expense of AFOV which is 45deg.  That of course matters less at high magnification.

The pic of the SLV shows also the adaptor for ease of use in all my 2” diagonals.

The Test

3.10 to 4.10am, Thursday – ED80 on Skytee II.  Clear, but very cold!

Target – waning gibbous Moon at about 55deg (so observing chair in use for comfort).  Concentrated on the terminator region.

4mm TV DeLite, x120 / 0.52deg

No loss of focus across the FOV – lovely sharp view – very slight “wobble” due to turbulence.

3mm WO SPL, x160 / 0.34deg

Hardly any loss of focus across FOV – bit more wobble – slight signs of “floaters”.

2.5mm Vixen SLV, x192 / 0.23deg – Exit Pupil an acceptable 0.42mm

Again, almost no discernible loss of focus across the FOV, and a bit more wobble – floaters more noticeable, but not really detrimental to the view. 

In Conclusion….

The DeLite gave a wider sharp view, as would of course be expected with lower magnification and with seeing effects being less pronounced, but the Vixen performed well giving clear detail of the terminator and other features such as the Alpine Valley.  A worthwhile addition to the armoury!

Doug.

[Ags]

I keep thinking I should get an SLV 2.5 for my ZS66, but I am waiting for a turret that works better than the Baader Q Turret. The eyepiece should help a lot with double stars!

[Mr Spock]

I have one on the way along with a 6mm, 5mm and 4mm  

[NGC 1502]

I have an original version Vixen LV 2.5mm.  It gets used with my ED80 to give a very high 240x for splitting tight doubles. Too high for most objects but brilliant at what I use it for.

The later versions like the SLV addresses the only criticism I have of the original LVs, that’s the roll down rubber eyecup, rather than the better screw down.

Ed.

[Louis D]

If the NLV/SLV top screwed down flush with the eye lens like the old LV roll down eye cup, then I'd have no gripe against it.  However, just like the BST Starguider eye cups, it does not, and so it robs about 4mm of usable eye relief from the eyepiece.  That's enough to go from comfortable to unusable for an eyeglass wearer like me with deep set eyes.

[NGC 1502]

1 hour ago, Louis D said:

If the NLV/SLV top screwed down flush with the eye lens like the old LV roll down eye cup, then I'd have no gripe against it.  However, just like the BST Starguider eye cups, it does not, and so it robs about 4mm of usable eye relief from the eyepiece.  That's enough to go from comfortable to unusable for an eyeglass wearer like me with deep set eyes.

Good point, and would have been easy to sort that at the design stage.

[MercianDabbler]

I have a 15mm SLV and I like it a lot.

Mine did not come with a tin of soup though. Did I miss out?

[Ags]

My 9mm and 12mm NLVs came second hand from the UK with a nice helping of VAT added at the border. But no soup 😐

[cloudsweeper]

9 minutes ago, MercianDabbler said:

I have a 15mm SLV and I like it a lot.

Mine did not come with a tin of soup though. Did I miss out?

Etiquette requires that EPs are photo'd with a can of beans, but we were fresh out of beans!  😉

Doug.