Greasy eyepieces?

[StarBru]

I recently purchased previously owned BST Agena 27mm Starguider and BST 16mm flat field eyepieces. On inspection, I noticed they both could use a little cleaning. While cleaning the 16mm last night, the optics immediately had a coating of clear grease on them, especially the bottom lens. It took quite a while to get the grease off and I also noticed some grease on the 27mm as well, although not as much.

I had heard that some eyepieces had grease with the eyecup design but I was not aware these eyepieces had that problem, and why would the bottom lens get grease on it when I used a different cleaning cloth for the top and bottom?

Does anyone have any experience with this? Any suggestions on how to clean these types of eyepieces in the future without getting grease on the lenses? It's annoying to say the least.

[Lady Fraktor]

That is a new issue!
Have you tried cleaning with some Zeiss Lens Wipes?

[StarBru]

I used the optical cleaning cloth that came with the eyepieces. They were clean, but after cleaning these eyepieces I noticed the inside of the twist-up eyecup had a sticky grease all around.

I do not have the Zeiss brand. Where can I get them?

[Lady Fraktor]

You should be able to find them in Walmart or camera shops.
I would try to remove the twist up eyecup and remove as much of the grease as possible.

[StarBru]

Okay, thanks!

[Bigzmey]

Amazon also sells them. Zeiss wipes work great.

[bladekeeper]

I get my Zeiss lens wipes at Walmart. A box of 200 is pretty darn cheap. They work well on eyeglasses too.

And reading glasses...

[StarBru]

My daughter bought a pack of 50 Zeiss lens wipes for me while she was at Walmart today. Thanks everyone, now I know where to buy them! They look similar to some other lens wipes I have bought online, and I can wait to try them!

[pakarinen]

The eyecup had grease on it and not the lenses?

If it was just the eyecups, I'd suspect somebody had make-up or lotion or something on when they were observing. Revolting thought that their goo would still be on the EPs, but should come off easily.

[StarBru]

The eyecup had grease on it and not the lenses?

If it was just the eyecups, I'd suspect somebody had make-up or lotion or something on when they were observing. Revolting thought that their goo would still be on the EPs, but should come off easily.

The grease is not from makeup or lotion. The eyecups twist up. The grease is in a recessed inside section of the eyecup, that when twisted up are exposed and it seems like the same type of grease that is used on Chinese made refractor focusers. The grease must have migrated to the very outside perimeter of the eyepiece lens on the top. I can't imagine how the grease ended up on the bottom side of the lens unless I accidentally contaminated it which is the most likely scenario even though I don't want to admit that!

Lesson learned, though. I am going to take apart the eyecups if I can, and remove all the grease so that it won't happen again.