Support Astromart! | Log In | Help
Astronomy NewsTelescope ClassifiedsTelescope AuctionsTelescope Articles & ArticlesTelescope Articles & ReviewsTelescope and Astronomy ForumsAstronomy Events Calendar
View Categories
Browse By Location
Place A New Ad
Display Preferences
Search Classifieds

User Name:

Password:

Save Login
 
New to Astromart?
Register an account...

Terms of Service
Privacy Policy
Help & FAQ
Astronomy Links
User Profiles
Top Users List
Sponsors
Supporters
RSS Feeds

Home > Classifieds > Astromart Classifieds > Eyepieces > Classified #710810

For Sale: Ball Eyepieces, 4.4mm and 7.4 mm [SOLD]

Please Log In to view the details for this classified ad.
Don't have an Astromart account? Click here to create one

Hi,

I have 2 ball eyepieces for sale ($40 each) that I constructed using a 6 mm Edmund BK7 high-tolerance ball (4.4 mm focal length) and a 10 mm BK7 ball (7.4 mm focal length). The housings are in good shape (the 10 mm ball housing has a scratch on the upper black anodized surface and some dust shows in the photos). The glass is in pristine shape. Siebert Optics sells a similar design with the designation "Planisphere Series". The eyepieces come with top caps only (pictured)

If you don't know about this design do a google search on single element eyepieces for some info.

I will give first preference to buyer who is interested in purchasing both eyepieces.

You will notice that the balls are slightly recessed in the housing. I prefer this design over the protruding design to limit greasing up from my eyelashes. It also helps restrict the view to the center of the field due to off-axis aberrations.

Thanks for looking
 

Back to Listing

All times are in (GMT-8:00) Pacific Standard Time Zone  
Astronomy News | Telecope Classifieds | Telescope Auctions | Telescope Reviews | Telescopes | Telescope and Astronomy Forums | My Account | Help | RSS