Orion Edge-On Flat Field Eyepiece 16mm

4.0 16mm Edge-On

Nice contrast, Nice FOV, Price, Twist-up eyecup

Coma is evident in fast scopes

This is a nice eyepiece for observing globular clusters. The fit and finish are very nice and the coatings are very good with no flaws whatsoever. The eyecup is a twist up type and feels fairly rugged and the eyepiece is fairly light for its size. I tried the eyepiece in 2 scopes, an f/12 Maksutov and my f/5 dob. I placed it in the Mak first and I immediately noticed the nice velvety black background and the perfect pinpoint sharp stars. They were perfect all the way to the edge with a nice contrasty view. Very nice job in the Mak. The view of Saturn was very nice with bands visible on the planet and the Cassini division was very noticeable. I waited for M13 to rise and the view was amazingly sharp with stars resolved to the core. Now in the f/5 dob I got the nice contrasty view but I could see coma starting at about 80% out towards the edge. If you have an f/8 or slower scope I would really recommend this eyepiece.