views on Orion Premium ED 102mm f/7 Refractor

Robert_T · #1 19-05-2008, 12:47 PM

Guys, has anyone had any experience on the Orion Premium ED 102mm f/7 Refractor... Bintel have these for $1295. A four inch with fast F7 sounds good for imaging?

regards,

Rob

[1ponders] (Paul) · #2 19-05-2008, 01:29 PM

Looks like a very nice buy Rob. Tell you what, you buy it, I'll test it and let you know.

Seriously though, if you get it, see if you can find someone with a WO III 0.8 focal reducer to try on it. It should work well and dropping down to f5.7 would be a big speed bonus and still keep your focal length to 570mm for those nice close and personal shots

Robert_T · #3 19-05-2008, 02:17 PM

Quote:

Originally Posted by [1ponders]

Looks like a very nice buy Rob. Tell you what, you buy it, I'll test it and let you know.

You've got a generous heart Paul... you could have suggested I do the same with a 110mm WO oil space triplet

On the reducer I often wondered how you get a faster focal ratio but supposedly a flatter image - is that right

[1ponders] (Paul) · #4 19-05-2008, 05:38 PM

Yes the WO Focal Reducer is also a field flattener.

http://www.williamoptics.com/accesso...troimaging.php