RKE eyepieces---Are they any good?????

To all,

I have never before monitored this forum so forgive me if it appears I am just bringing up a very old subject yet another time. The Edmund RKE eypieces have been on the market for very many years but I have never seen one in person, nor have I ever used one. I see them for sale from time to time on Astromart. Does this mean they are still considered good instruments???? I would appreciate anybody's comments about where they fit into the broad spectrum of currently available eyepieces. Some kind of evaluation please, even if it is just personal opinion. Give them a rating, like from 1 to 10, if you feel like it. I just want to get a basic idea of how good or bad they are generally considered to be.

TIA,
David Kernberger

David Kernberger said:

To all,

I have never before monitored this forum so forgive me if it appears I am just bringing up a very old subject yet another time. The Edmund RKE eypieces have been on the market for very many years but I have never seen one in person, nor have I ever used one. I see them for sale from time to time on Astromart. Does this mean they are still considered good instruments???? I would appreciate anybody's comments about where they fit into the broad spectrum of currently available eyepieces. Some kind of evaluation please, even if it is just personal opinion. Give them a rating, like from 1 to 10, if you feel like it. I just want to get a basic idea of how good or bad they are generally considered to be.

TIA,
David Kernberger

David,

They are nice eyepieces, especially if you have a "slow" telescope. They are essentially a Kellner, and do not work as well as more expensive eyepieces on fast instruments. I certainly wouldn't recommend using one on a f/4 or f/5 instrument. We have several with the club's 6" f/8 loaner Newtonian and they work well on it.

Clear skies, Alan

Please, every one!!!!!!! I have stated that no use of the initials or names can be used on the forum, thanks!

David,

Every EP (or design) seems to have a niche where it really excels. The RKEs fall into this IMO. They only have a 1/4 wave MgF2 coating instead of full multi coatings, so they don't transmit as much light as multicoated ones. But this is an advantage in some situations. Plus there is a school of thought which says that multicoatings, although great for thruput and seeing faintest stars and nebula, is a disadvantage for subtle details on planetary atmospheres.

For sure, on-axis my RKEs show as good...sometimes better, subtle details on both planets and moon even when pitted against premium EPs. This is in both slow and fast scopes (my fast one is f/4.7).

Also, the 21.5mm with 2X Ultima showed me the best rendition of Trapezium E & F than even highly touted Premium EPs have. So depending on the target and scope and conditions, sometimes these little EPs beat them all. For what it's worth, while overall they are not the "best" eyepiece, for some applications they are and they are a line I won't part with in my case.

-Bill

My experiences are similar to others.

Plossl's have a bit larger AFOV, that's a bit sharper over more of that field in faster scopes. RKE's are a bit more comfortable to look through.

Nice ep's. Somewhere between a UO type ortho and a well made plossl IMHO.