This auction is for a very early 1980s University Optics (Nihon Seiko of Japan) 2-inch 13mm Wide View Plossl with multi-coated optics.

Though this is labeled "University" it is, in all truth, a "University Optics". If you are a fan of this long-running classic ocular manufacturer/brand, you will see the font, color schematic, and the "Made In Japan" decal will match all other UO eyepieces of this era; about 1976-1983.

Nihon Seiko is the optics firm that made nearly all of their eyepieces and finder objectives, as well as Unitron's and the older Celestron Ultima line.

Specs...

Barrel Size:  2-inches

Design:  4-element plossl with multicoated optics

Exit pupil:  13mm

Eye relief:  6mm (to get the entire field into complete view)

Field of view:  58-60 degrees

Construction:  aluminum and brass. Teal grip ring is aluminum

Standing height:  2.76-inches

Weight:  7 ounces

The 2" barrel University Wide View Plossls are virtually unheard of. I have on quite rare occasion, come across okay-to-great conditioned examples of the 1.25" barrel models and they also have the same widefield view. However, in the 1.25" models they were aperture stopped and so the outermost 5-8 degrees field of view lacks resolution due to the light trying to bend around the stop.

In this 2" model, this issue seems to be significantly less apparent. It is not as sharp to the very edge as a TeleVue Radian, but it is very close. And one should keep in mind these plossls were ahead of their time when plossls were barely coming back into the market as Kellners and Orthoscopics were the mainstream class.

And so having a 2" eyepiece barrel capable telescope back in the day was a rare customer indeed!

It should also be noted that this eyepiece is barely marginal in being a true "Wide Field" eyepiece. Today, this is generally applied to 65-degrees to 72-degrees fov optics. As stated earlier, however, this was an eyepiece giving about 60-degrees fov when nearly all other eyepieces, even in 2" form (like the very rare Celestron 60mm and 70mm kellners) were giving under 50-degrees fov.

Being this is a plossl, it will behave VERY WELL in all types of telescopes with focal ratios from f/4 to f/15. I would say longer than f/15, but I have never seen a mainstream telescope that has a 2" focuser barrel with a focal length over f/15. The 13mm focal length will be perfect for the study of globular and compact open clusters, all types of nebulae; emission, dark, planetary, and reflection, it is a great eyepiece for high medium power when seeing is not at its best for the planets, and I had quite a few fine views of the primary galaxies such as M31, M51, M94, and NGC7331.

For the collector, this is a highly rare find as I have yet to ever see the 2" models offered for sale, which are now LONG out of production. 

Packed with great care.

Combined shipping offered.  Higher cost in shipping indicates this ocular MUST be insured to all destinations. To my foreign friends: this eyepiece will only go priority international so it may receive full insurance as this ocular cannot be replaced, and no, it WILL NOT fit in a small rate box, so don't ask please.