I'm confused

Picked up a 10 yr. old Celestron ST80 to test the water for a quick grab & go scope with no electronics. Looks the concept will work for me.

Now I want to upgrade and I've figured out most of distinctions (semi-apo vs. apo., ED, FPL-51 vs. FPl-53, etc.) but 2 have me stumped.

Can anyone explain what "SD" and "SF" mean. I think only WO uses these abbreviations.

SD = SuperDuper
SF = SupercaliFragilisticexpealidocious

Thanks. That certainly clears things up. :S

Great One, Ed a great one. Made me laugh. However, I too, would like the answer to that one.

Roger in Tampa

Can anyone explain what "SD" and "SF" mean. I think only WO uses these abbreviations.
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I believe that SD is an actual term used and means "special dispersion" or maybe "super low dispersion." My understanding is for WO: SD=FPL51

Never seen the SF on one of their scopes, do you have a link? WO normally uses F to mean "Fluorite" which is actually FPL-53.

If you ask about specific models, probably someone can offer their experiences.

Jon

The last term was created by that famous astronomer Mary Poppins!! 8O

Confused? Heck, I'm always confused.

One thing I'm straight on: An FS78 makes a heckuva nice "Grab and Go out to the backyard" scope. There's one going cheap on AM now. Jump on it.

It'll save you doing all this SD, SF, alphabet soup research and then still not knowing whether a scope is any good.
FWIW
Bob (Very happy FS78 owner)

Really, these terms have no specific meaning and therein lies the problem. One mans ED is not an ED to another. What is ED, it is not completely color free, so how do you determine ED or Semi-APO, Semi-ED, ED-Achro, Ect.
I think that all these marketing terms should be avoided and that just the actual performance figures should be used. But then I guess you have to determine what percentage of correction is required to meet a specification and how is this determined?
Really you need either to test it yourself or have someone that you trust as a reviewer give you his opinion on the scope. But still, opinions are just that and it is still your eye that must be satisfied.

Can anyone explain what "SD" and "SF" mean. I think only WO uses these abbreviations

SD = lots of bucks

SF = lots more bucks