Vixen SSW Ultra Wide Angle Eyepieces: Review

[John]

It's taken me a while to complete this review but I wanted to give these a thorough examination.

The Vixen SSW Eyepieces

Introduction

The Vixen SSW’s were first seen at the Photokina Show, Cologne, Germany in

September 2014. It was quickly revealed that these would take Vixen into ultra

wide angle territory in the form of an 83 degree apparent field of view. There were

also hopes that Vixen would find a way to avoid the rather short eye relief that so

often goes hand in hand with ultra wide fields of view, much to the frustration of

those who wear glasses when observing and also those who like to be able to see

the full field of view without having to press their eye right up against the eyepiece.

Whether the SSW’s replace or compliment Vixen’s wide angle offering, the well

regarded LVW range, now seems in a little doubt as I understand that, for the time

being at least, the LVW range will continue to be available.

The current SSW range comprises of the 14mm, 10mm, 7mm, 5mm and 3.5mm.

These are all 1.25” fitting eyepieces. Whether there are plans afoot for longer

focal lengths is not known. If the range were to extend beyond around 17mm, the

larger barrelled 2” format would be required to maintain the 83 degree field.

As for what SSW stands for, well Vixen aren’t saying. We can guess that the final

S and W are possibly for “Super Wide” but what is the first S for ? “Special”

perhaps ?

Initial Impressions

The first things that draw your eye with the Vixen SSW’s, once they are removed

from their fairly conventional boxes, protective polystyrene and plastic bags, are

the striking colour scheme and their compact size and modest weight, compared

to some other ultra wide eyepiece ranges.

The colour scheme makes a connection between the focal length of the eyepieces

with wavelengths of light, eg: Red = the longest focal length, through to, Violet

= the shortest. This has been done before in eyepieces but perhaps not so

strikingly as with the SSW’s. A nice touch but of no practical use in the dark

unfortunately where both the colours and the clearly labelled focal lengths

become irrelevant and the size of the eyepiece becomes the best indicator of what

focal length you are holding.

Here are the Vixen SSW’s in all their multi-coloured glory (the eye cups are shown

at various heights to illustrate their range of travel): 

Vixen’s specifications for the SSW range are as follows:

Apparent Field of View: 83 degrees

Eye Relief: 13mm

Weight: 210g (14mm) - 230g (3.5mm)

Light Transmission: 99.5%

Glass Type: Low Dispersion

Coatings: High Transmission Multi-coatings on all air to glass surfaces and

special coatings on glass to glass cemented surfaces

And here are some measurements which I took myself:

Height: (eye cups fully extended): 80mm (14mm) - 110mm (3.5mm)

Width (widest part of barrel): 52mm

Eye lens diameter: 26mm - 27mm (slight variation across the range)

Eye cup twist-up travel range: 7.5mm

To put the above dimensions and weight into context, middle eyepieces of the

SSW range are around the same size and weight of a regular 32mm plossl

eyepiece and around 25% heavier.

The Vixen SSW’s are priced at the time of writing at £249.00 each.

This is the 14mm SSW:

The rubber eye cup is soft to the touch, and it’s top rim is 5mm wide. The rubber

has a little give to it and is comfortable to rest your eye socket against, which is

just as well as this is necessary to see the full field of view I found (more on his

later).

The rubber section of the eye cup is securely mounted on a metal anodised

section which gives a twist-up action that is smooth but firm and consistent

across all the eyepieces in the range, or at least the examples that I have used.

There are no click-stops in the motion - the eye cup can be positioned exactly

where you want along it’s range of travel and it will stay there until you change it’s

position. This is the best implementation of this Vixen twist-up eye cup that I’ve

seen. Gone is the slightly loose movement of the NLP, NLV and SLV Vixen ranges.

This now feels and operates with precision which matches the overall eyepiece

build.The twist-up action, which takes the eye cup through it’s 7.5mm travel range,

requires just a half turn of the eye cup in total.

The SSW eye lenses are not recessed within the top of the eyepiece barrel but at

it’s lowest position the rim of the rubber eye cup is around 5mm above the top

surface of the eye lens. The upper surface of eye lens seem much flatter

compared to the convex figure that many ultra wide angle eyepieces use. This has

some significance because eye relief is measured from the centre part of the

upper surface of the eye lens and, if it’s deeply concave, you don’t always get as

much eye relief as the specification promises!

Here is the 10mm SSW:

The lens coatings seem rich and high quality showing purple to green tints

depending on the angle viewed at. Very similar tone to those used on other top

quality eyepieces that I regularly use. The quality of build and finish of the Vixen

SSW’s seems really excellent to me.

The metal parts (including the colour coded sections) are satin finished on the

body and the 1.25” barrels are heavily chromed with the word “Japan” stamped

around their lower section. There is a shallow security recess cut into the

eyepiece barrels. This is wider than many I’ve seen at 8mm across and the lower

edge is gently cambered to reduce the possibility of the barrel catching on

compression rings during eyepiece insertion and removal. Some would prefer that

these security recesses were not there at all though. I didn’t experience problems

with the Vixen SSW’s “snagging” on my compression ring fittings in general.

The SSW chrome barrels are a little shorter than some other designs being 25mm

deep from the “shoulder” of the eyepiece body to the end of the barrel.

Inside the chrome barrels, the internal blackening is comprehensive and really

well applied. It includes the filter threads and the lens retaining rings which seem

to be well designed and neatly executed.

Looking through the optics of the

eyepieces, internal light baffling seems to be really effective. With the quality

coatings of the lenses, looking down into the eye lens is like looking into a

darkened well.

This is the 7mm SSW:

With regard to eye and eye cup positioning with the Vixen SSW’s, I don’t wear

glasses when observing and, as is usually the case, I found that having the Vixen

SSW eye cup close to it’s highest position, worked best for me. Just a small turn

down from the upper most position was about right for me to be just about able to

see the whole field of view without experiencing any kidney beaning or other black

out effects.

I did find holding the correct eye positioning with the SSW’s was harder work than

other similar eyepieces that I have used. There was little margin for error is

seemed, just a mm or two further in and I started to experience some of the

curved black zones known as “kidney beaning”. With the eye cup extended to it’s

fullest extent, seeing the whole field of view required a little more effort on my part

than I’d have ideally liked. I’m glad the eye cup positioning did have the

adjustment built into it’s design - it was needed. Unfortunately I can’t see the Vixen

SSW’s being suitable for most who wear glasses when observing.

Looking through the eyepieces in daylight (not in a scope) the edges of the field of

view are sharply defined. No blurry field stops with these eyepieces. Night time

views confirmed this. In daylight, the apparent field of view of the SSW’s looks

comparable with the 82 degree eyepieces that I own and noticeably wider than 70

degree eyepieces.

The 5mm Vixen SSW:

Each SSW eyepiece body section incorporates a 20mm wide rubber grip which

has a hexagonal profile. This shape prevents the eyepiece from rolling when left

on it’s side on a firm surface. It also makes for confident handling at night and in a

gloved hand. The top and bottom dust cap fit snugly and the eyepieces could be

held upside down and shaken without dislodging the top cap. The top cap

remained a good fit what ever position the eye cup was in.

The colour coding used on the SSW’s body sections will not be to everyone’s

taste of course but it is finished to a very high quality in anodised metal with quality

screen printing of the brand, model, focal length and apparent field of view. The

black parts of the eyepiece body (which vary in extent with the focal length) are

again impeccably finished. I am strongly reminded of the quality of the other top

eyepiece ranges that I own when I look at the SSW’s. They certainly feel like

premium eyepieces.

Although not being at all heavy compared with some other ultra-wide models,the

Vixen SSW eyepieces do have a very nice “heft” in the hand. You do feel that

these are quality products, as befits their price tag of currently around £250.00

apiece.

Finally, the 3.5mm SSW:

Using the Eyepieces

To assess the performance of the Vixen SSW range I used them over a number of

nights in my 3 main telescopes, a 12” F/5.3 dobsonian my 4.7” and 4” F/7.5 and

F/6.5 ED doublet refractors. I viewed a wide range of astronomical targets

including nebulae, galaxies, star clusters, binary stars, the Moon and the planets

Saturn, Neptune und Uranus. I mixed familiar and easy objects with some more

challenging ones and a few that were close to or at the threshold of what I can see

with my scopes from my back garden observing site, which is affected by the

regular run of challenges including some light pollution, trees, neighbouring

houses etc. In total I’ve probably spent around 10-12 hours observing with the

Vixen SSW’s so feel I’ve got to know them reasonably well. For comparison

purposes I have my Tele Vue Ethos and Pentax XW eyepieces in the equivalent or

similar focal lengths.

As a range the Vixen SSW’s seem to be pretty much exactly par-focal with each

other with only the tiniest focus adjustments being needed after switching focal

lengths. They also seem to reach focus at a fairly conventional spot in the focuser

travel, comparable to many other eyepiece ranges eg: the Pentax XW’s.

The apparent field of view of the Vixen SSW’s is 83 degrees and the eye relief is

stated as being 13mm across the range. As I mentioned above, with eyepieces

like the SSW’s, that have adjustable height eye cups I’ve found that I generally

need the eye cup towards the top end of it’s range to be able to see the full field of

view without unwanted effects.

Some eyepieces are quite sensitive to eye positioning and I found that the Vixen

SSW’s belong to that category. With the eye cup fully extended I could just about

see the whole of the 83 degree apparent field of view but I needed to press my

eye quite firmly onto the eye cup to achieve this. When I tried twisting the eye cup

further down a few mm the full field of view was a little easier to see but those

kidney shaped black areas soon appeared, which was a little frustrating. Overall I

feel that eye positioning with the SSW’s is rather finicky, a little more than I’d like if

I’m honest. You have to think about placing your eye to the eyepiece and take

some care to retain the optimum position. This can detract slightly from

concentrating on the object being viewed I felt.

On the positive side, these eyepieces did not seem to show a noticeable bright rim

around their field stop edges, as many ultra wide field designs seem to. This

makes them more suitable for daytime use than some other designs.

In terms of the optical performance of the Vixen SSW’s I think I have two stories to

tell.

The first story concerns performance over what I would estimate to be the central

75 degrees or 90% of the field of view and it’s a very positive tale. In this, the

majority of the visible field, the views are superb of both solar system and deep

sky objects.

The tone of the optics seems to be neutral. Light scatter and glare around bright

objects is really well controlled. Light transmission levels seem really high - Vixen

claim 99.9% overall transmission and across the range the SSW’s seemed to live

up to that and matched the Pentax XW’s and Ethos ranges fully in this respect.

Faint and extended deep sky objects showed excellently across the field of view. I

was able to view point sources down to magnitude 13.5 and the Vixen’s did just as

good a job in allowing me to hold such dim objects with direct vision as the other

premium competitors did.

Low and high contrast planetary and lunar features were well defined and I could

not see any ghosting in any of the Vixen SSW focal length. Putting a bright object

just outside the field of view (ie: just hidden by the field stop) showed that light

flaring was well controlled with these eyepieces too. There was little sign of the

bright object until it popped out into view whereas with some eyepieces you can

see a fair amount of glare from such objects well before they are actually in the

field.

I also looked carefully for signs of brightening of the background sky at the edges

of the field of view (Edge of Field Brightening as it’s known) but I could not detect

this effect. Additionally I checked to see if faint objects remained a consistent

brightness as they traversed the field and I could not see any signs of variation in

this either.

Setting aside the fussy eye positioning, I felt that the performance over 90% of the

field of view was very like that of the Pentax XW’s and provided very high quality

views of a wide range of astronomical objects.

The second story is somewhat more complicated and concerns the outer 10% or

so of the field of view. To achieve an ultra, or hyper, wide field of view free of

severe distortion, optical designers have to make some compromises and the

most common compromise that I see in such eyepieces is a more modest

distortion called rectilinear distortion, sometimes known as “pincushion” distortion.

This has the affect of causing objects to very gradually become elongated as they

get closer and closer to the outer edges of the field of view.

All the Vixen SSW’s seemed to show this distortion in the last 10% or so of their

fields of view. When viewing Saturn, for example, the planet and it’s rings appear

to stretch out as I allowed it to drift, as if the image was on an elastic surface. The

elongation is away from the centre of the field of view. This effect is present to

some extent in all very wide angle eyepieces that I’ve used and, to me, is

acceptable provided that objects remain sharp and free of other defects, ideally

right up to the edge of the field of view.

The complexity in the Vixen SSW’s case is that in addition to the modest

rectilinear distortion, the outer 10% of the field of view also shows some

astigmatism. The visual effect of this is that stars become very slightly “cross”

shaped as they near the field edge and when viewing the Moon, planets, and

double stars, a degree of sharpness and resolution is lost when the object being

viewed gets close to the field stop edge. Again this was present across the all the

SSW focal lengths.

To add to the above, I also detected small amounts of chromatic aberration, false

colour, creeping in around brighter objects, again in that last 10% of the view. This

was noticeable when viewing the Moon and you could see the black shadows in

the floors of craters on the terminator gain a blue/purple coloured fringe as they

drifted towards the black field stop edge while the bright highlights acquired a

yellow/orange tinge. I also saw similar effects when viewing bright stars such as

Vega and the well known “double double” pair of Epsilon Lyrae. I should add that

this effect was seen when using newtonian optics (which are colour free) as well

as with my ED doublet refractors. This was repeated in all the Vixen SSW

eyepieces however it was more noticeable when using the shorter focal lengths

probably because of the higher magnifications generated. This was only in the

outer reaches of the field of view though.Otherwise the field of the Vixen’s seems

free of eyepiece generated false colour.

I looked carefully for the above effects when viewing a variety of objects with my

12” F/5.3 dobsonian and my 4” and 4.7” ED refractors which have focal ratios of

F/6.5 and F/7.5 respectively. The astigmatism was less pronounced as the focal

ratio became “slower” however the rectilinear distortion and the slight chromatic

aberration remained fairly consistent across all the scopes.

If the Vixen SSW’s had been a less expensive model I feel that the above outer

field issues would be considered fairly insignificant, however the retail price of the

SSW’s puts them alongside the very best of the wide and ultra wide field

eyepieces, competitors such as the Tele Vue Delos and Type 6 Naglers, the

Pentax XW’s and the Vixen’s are quite a bit more expensive than the William

Optics UWAN, Skywatcher Nirvana and the Explore Scientific 82 degree ranges.

None of these eyepieces are perfect in every respect of course (no eyepiece is)

but I do feel that the optical issues I saw in the outer fields of the Vixen SSW’s and

the rather fussy eye placement might be enough to make a prospective buyer look

harder at the alternatives available for £250.

Summary

I really did like styling, the compact size and relatively light weights of the Vixen

SSW’s. I think their build quality and handling is very good. Their optical

performance in the majority of their field of view is excellent and they showed

some very challenging astronomical targets as well as some of the best eyepieces

around. Given their cost, I felt a little disappointed in their edge of field

performance though and the eye positioning was more challenging than perhaps

than it ought to be. Vixen don’t seem to have been able to break the link between

shorter eye relief and ultra wide angles of view.

I’m very grateful to First Light Optics for the extended loan on the Vixen SSW’s

which has given me the opportunity to test them reasonably thoroughly and to

report back to the forum.

As ever I must add the caveat “Your Mileage May Vary” because that’s how it

seems to be with eyepieces !

John Huntley

October 2015

Here is a MS Word (7.8mb !) file    :

Vixen SSW Eyepieces Review.doc

Also a PDF version. It's somewhat smaller but the formatting of the text and photos is not quite the same as the original - please bear with it !:

Vixen_SSW_Eyepieces_Review.pdf

[AndyH]

Thanks for putting the time & effort into this John. Always appreciated . I shall take  a lie back on the sofa, coffee in hand and delve into it.

Cheers,

Andy

[jetstream]

Excellent report John, thanks.

[John]

Thanks folks

I've just noticed one or two glitches in the report - hope these don't detract too much from it's meaning !

[Space Hopper]

Thank-you for posting your review John.

Very informative.

I've been considering buying a pair of 14s and possibly 10s, for Binoviewing purposes ONLY.

I actually tried out the 14s over at the Vixen stand at the IAS.

My biggest concern is one you highlighted : the tricky eye placement.

I do like the small compact size of these though.

But at £250 they are simply too expensive. Can't see many people forking out this much. I can see them dropping quickly to the £200-£225 price band.

Not when TV Delos / Nagler can be purchased cheaper. Just paid £232 for 10 Delos at the IAS (ok that was discounted a bit)

I  now have a pair of Delos 10s to try in the Mk V but haven't had chance to use them yet.

Just the weight is an issue with this set up. Its going to be around 2Kg hanging off the focuser.

The SSW would certainly have been a better size.

Theres too many choices, and ifs and buts in this hobby !!!!

[jabeoo1]

Thats a well written report John, thanks for doing the hard work.  I was on the fence over the 7mm and your review has saved me some money ! 

[Chris]

A great read John, thank you for taking time to do such a thorough review I don't think they're for me if they have fussy eye positioning, and the edge performance should be better for the price like you say. 

[Mr Spock]

Great review.

I think given the price a T6 Nagler seems a better deal. I was hoping for more - an LVW they are not and, a bit disappointing really.

[Pig]

Fantastic review John as always

I did go and have a look at the SSW range during my visit to Astronomy Show held in Warwickshire a couple of weeks ago and I too was pleased with the build quality and how the SSW  felt when held, they do have a very nice balanced weight to them.

I was going to buy one but I was put off by the shorter eye relief as I find this an important factor for me. I am a little surprised by the chromatic aberration you mention in your review as the SLV range do not show any at all, I guess this is easier to control with the SLV being 50 degrees.

[YKSE]

Excellent review as always, John,

A couple of questions:

About "bright rim at field stop", is it the so-called "Ring of fire"? If so, what's the color of it? Is is visible in day time too?

And the"kidney bean" effect, do you see it in day time use too?

[Damo636]

Another fine report John, thanks very much! I was contemplating the 7mm but think I'll now pass. Any chance you'll get to check out the new Baader Morpheus in the near future?

[F15Rules]

Great review John, and a good read as ever .

Pinning my colours to the mast, I read this as an interested bystander, as I wouldn't be buying these new - but I suspect many others will be in the same boat, ie as potential future used purchase buyers. I've just acquired a pair of LVWs at 5mm and 8mm and am delighted with them. I find the 65 deg field to be my "sweet spot" field of view, and the LVWs are sharp right to the edge in my scopes. So my question is, if the new SSWs are not sharp over the last 10%, or c 8.3 degrees, the effective sharp field is only c 74-75 degrees, so not that much more than the LVWs - which have 20mm of eye relief to boot! So it's LVWs for me.

It's good to see they are still made in Japan, as I thought I read somewhere that these were now outsourced to China, like most other things. THe build does look to be very good, but I still don't like the rainbow effect, which to me cheapens the look and as John says, is irrelevant at night in terms of product identification.

At the prices published, I think the established tier  1 ranges of Televue and Pentax have little to fear from this new range, which is a shame. I just hope Vixen do continue to make the LVW range, as they are worthy competitors to both of the above brands IMO.

Dave

[Thonolan]

Excellent review, John. I was really looking forward to reading this one

Your mention to tricky eye placement is consistent with Don Pensack's first impressions on Cloudy Nights. I really like the look of these eyepieces and the build quality seems to be superb, but I don't think I'll be buying any of them at the current price.

[jabeoo1]

Its a shame really, I had high expectations pinned on these. The 7mm XW or TV Delite seems a better option now (as stated above).

[John]

Excellent review as always, John,

A couple of questions:

About "bright rim at field stop", is it the so-called "Ring of fire"? If so, what's the color of it? Is is visible in day time too?

And the"kidney bean" effect, do you see it in day time use too?

Thanks Yong

The SSW's don't show the "ring of fire effect". Maybe my text was not clear on that ?

The "kidney bean" effect happened both at night and in the daytime when I twisted the eye cup down a few mm to help see the full field more easily. It was not permanently there but the dark shapes popped into view if I moved my eye a little too far inwards. It was more noticable in the daytime but I noticed it when I was viewing the Moon. When the eye cup is fully extended it goes away but then I was having to try harder to see the full field of view, harder than I'd like, ideally.

Hope that helps

[John]

Another fine report John, thanks very much! I was contemplating the 7mm but think I'll now pass. Any chance you'll get to check out the new Baader Morpheus in the near future?

Thanks Damo.

I'm hoping to have a look at some of the Morpheus eyepieces in the near future

[gooseholla]

I suspect at those prices, the ES 82 range will remain the favourite alternative to Naglers for some time. Although they do look rather funky, but as you say completely useless in the dark. Also you seem to suggest their views compare with other premium eyepieces in the central 90%, so maybe a few will be willing to shell out the extra. For me, probably not. I think I would be an ES 82 buyer and save c. £130 on each eyepiece.

John

[YKSE]

Thanks for the clarifications. I misread your decriptions about ring of fire.

[Roy Challen]

Thanks for another great review John. I'm in agreement with some of the replies in that the SSWs seem to be a bit over priced.

For me, the main issue is eye placement. I have this problem with the ES 82 degree range although it's not too sensitive. Perhaps ultra wides just aren't for me.

The other thing for me would be the undercuts. Why did Vixen do this when the excellent SLVs have smooth sides? Anyone who owns a Takahashi prism will know why I say this.

[Star Struck]

An excellent review as always John. Thanks very much.

You can't tempt me buy them as they do seem overpriced for my budget.

[Chris]

Thanks for another great review John. I'm in agreement with some of the replies in that the SSWs seem to be a bit over priced.

For me, the main issue is eye placement. I have this problem with the ES 82 degree range although it's not too sensitive. Perhaps ultra wides just aren't for me.

The other thing for me would be the undercuts. Why did Vixen do this when the excellent SLVs have smooth sides? Anyone who owns a Takahashi prism will know why I say this.

Yep, I have the Tak prism diagonal and know exactly what you mean Roy The SLV's are a joy to swap in and out with this diagonal whilst anything with a taper or undercut is a bit of a pain.

[John]

An excellent review as always John. Thanks very much.

You can't tempt me buy them as they do seem overpriced for my budget.

I'm not trying to sell them !

They were loaned to me by First Light Optics to review and report back on. I've no commercial interest or links with any of the eyepieces or brands that I've reviewed on here or with First Light Optics. I expect you guessed that but I thought I ought to say it just to avoid any potential confusion !

[Piero]

Nice reading and very accurate review, John!

It will be certainly useful for people in the market for compact ultra-wide eyepieces. 

.. and glad to know that my naglers are still the best options for this type of EPs!  

[michael.h.f.wilkinson]

Very nice and balanced review. The eye relief killed the SSWs as an option for me. I will be looking at the Morpheus 14mm instead

[Saganite]

Thank you John for a very interesting and informative report. The decisive negative for me is the eye placement sensitivity,but with  the various problems at the edge of the FOV as well, I would seek alternatives with my £250.