Wollensak 12.5mm - Will it be any good?

[mdstuart]

Just bought one of these second hand..

WOLLENSAK 12.5MM 2" EYEPIECE - Surplus Shed

I am trying to get a 2 inch highish power lens that will work in my F5.

So this has 9 elements, only a 55 deg FOV so should be interesting..

Has anyone any experience with this eyepeiece? There is very little in the reviews etc.

Mark

[mdstuart]

Well it turns out to be fantastic, sharp to the edges. A fine high power 2 inch lens...

Well made. A real 2 inch lens not a 1.25 inch in a 2 inch body etc.

Perhaps the only issue is th elack of a rubber eye cup so to get all light out the way you need to make a ring with your fingers to block out the light!

Mark

[albedo0.39]

Hi Mark - thanks for posting the report and what a great find. Where on earth did you hear about this ? This size of lens is exactly the one I'm looking for and the focal length is missing in my collection. I'm also really interested to hear that's its sharp to the edges and perhaps it's down to having 9 elements (that seems an awful lot)

What is the image like in the centre ?

[mdstuart]

As with most stuff I bought it on e-bay for just under £60.

You can get them from surplus shed in the USA.

Yes the view was fine, lovely little spots for all stars throughout the FOV. NGC 6819 was super.

Yes 9 elements seems a lot but on comparison with my two 6.4/20 mm plossls it seemed I could see the very faintest stars so no appreciable loss of light transmission.

It is well built, all metal and not too heavy which is also a bonus.

Very little reviews on the net which is why I made this post originally.

The FOV is only 55 rather than the 68/80 of some other lenses but it feels much wider at the eyepeice than the plossls because of the design.

So I am really thrilled!

At 13.5mm it shows Jupiter as a 7mm accross disk so plenty big enough to see detail, smaller galaxies such as M32 look fine but as I said somewhere else you can fit M31 and M32 in the FOV just so it has a good wide field for a lens of the power.

Would not sell it now for less than £100!

Now to find a 2 inch very high power lens say 5/6mm..Ideas welcome.

Mark

[mdstuart]

Bring your scopes to Bristol and you can try it .. Will it still be amazing at F4?

[albedo0.39]

Bristol ? I hadn't thought of that, but it's a bit heavy (and not entirely a grab-n-go). Perhaps you are going to the SGL Star Party at Salisbury ? If so, I'd welcome a look through the EP whilst there

[PeterW]

You only need to get a 2" eyepiece for focal lengths >17mm or so (absolutely for >25mm). All the shorter focal lengths are in 1.25" only usually. Finding cheap eyepieces that are good <f5 is hard, looks like you found a good one!

Cheers

PEterW

[haitch]

You might not need 2" at short focal lengths but I must admit I fancy trying to put together a collection to save faffing with adaptors.

I shall be keeping my eye open for those.

I've just bought a 1.5x 2" barlow of the same brand off Ben Ritchie on here So I'll post on that when I've had chance to use it.

[mdstuart]

I would love to go to the Salisbury get together but it might not be possible with my wifes shifts. If I can pop down for a day I will bring the eyepeice.

I agree you do not NEED a 2 inch eyepeice below 25mm but it is nice not to have to change the adapter when switching between eyepieces and it feels good to look through the wide lens so I linke it.

Mark

[PeterW]

I have the opposite problem, a collection of 1.25 eyepieces and filters, I am looking for a long focal length, the 24mm panoptic is the only real option. There are lots of 2" options, but I don't want to even think of getting 2" filters....

PEterW

[haitch]

Well a 32mm plossl pretty much makes the most of a 1.25" tube so if you want a wider field than that you really need to move to 2".

My 1.25" 40mm Meade Super Plossl has the same FOV as my 1.25" 32mm Meade Super Plossl so pretty pointless.

[Toymaster]

So this is what is inside the Wollensak 12.5mm EP

Seems to work OK for me...

Adrian