FreeLists / az-observing / [AZ-Observing] Re: The Orion 120mm ED Refractor

[Stan Gorodenski <stan_gorodenski@xxxxxxxxxxxxx>]

I remember Orion had a 5" refractor that they called an ED(I think) 
5-10(?) years ago. It was in a white tube and was fairly inexpensive. I 
looked through one at RTMC and it seemed good to me, but I am probably 
not hard to satisfy in this regard due to my ignorance of really super 
refractors. For some reason they stopped producing it.

Last year when I was in NM I stayed overnight at the Oliver Lee Memorial 
state park south of Alamogordo. I got in late at night, and as luck 
would have it a person, Fred Sweeney, needed to have his vehicle jumped 
so he could charge the car battery in case he needed to take his wife to 
the hospital. He had an Orion 5" refractor set up. It had a white tube 
but was not the ED. Although not an ED I was impressed at the quality of 
the images, if you do not demand too much. When necessary, he used a 
lens from Orion that is supposed to reduce the chromatic abberation. If 
one is not too demanding, the Orion is probably a real bargain for the 
price.
Stan

DBogan3220@xxxxxxx wrote:

>Ive gradually learned over the years in the APO world you get what you pay  
>for. The Orion Catalog says they are using FPL 53 for the ED element  the 
>glass 
>I'm assuming its the Ohara brand out of Japan. If so that would  be a good 
>point. The question I would have would be what are they using for the  mating 
>elements. It is a triplet so that is a good point. Its a longer lens I  
>believe 
>its around F9 another good point. Here the maker could get away with  using 
>cheaper mating elements.This would keep the price down.  If it was  an F6 with 
>zero color error as in my AP 130 F6 the raw glass elements will  cost the 
>manufacturer more than what Orion is selling the scope for. Last point  is how 
>well 
>the figure of each surface has been executed and I would assume the  
>centering of each element is not an issue and last the construction of the  
>cell. Is 
>it Temperature compensated?These are details that need to be addressed  and 
>why 
>a current 5 inch APO that meets all the above criteria cost 5k and the  
>companies that make them are not getting rich doing it.  Last of course is  
>the 
>mechanics of the tube assembly. and the focuser light baffles and so forth.  
>This 
>I think is where the orion would cut the corners the most to save money and  
>increase profits.
>  
>
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