[Hitman]

Following is an exchange I had with Celestron's tech support. I am wondering why they even offer ED lenses @ over $100 adder if there is so little difference between the ED and non-ED systems. Any thoughts on this topic?


Posted on 26 Dec 2006 02:45 PM

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To the real-world user, is there a perceptable difference between the Ultima 100ED and the standard Ultima 100? I am considering the purchase of a spotting scope for use in rifle competition spotting applications and also for star gazing for my 9 year old son. Will there be a noticible difference bewteen images viewed in these scopes. I would go look at these side-by-side but the closest dealer is over an hour away and I am not sure they would have both of these scopes available.




Posted on 10 Jan 2007 02:37 PM

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WELL THERE IS NOT A VERY BIG DIFFERNCE IN THESES TWO SPOTTING SCOPES, TO BE PERFECTLY HONEST WITH YOU SIR I DONT EVEN THINK THAT YOUR SON WILL BE ABLE TO TELL THE DIFFERNCE BETWEEN THE TWO IF HE LOOKED AT THEM, THATS JUST HOW CLOSE THEY BOTH ARE WHEN IT COMES TO THE OPTICS.

 

[Willyboy]

ED Lenses

A few years ago I was looking side by side thru 2-3 quality scopes in the same price range. Then I looked thru a B&L Elite with ED glass. All the scopes showed bright, clear colors on a cardboard sign a block away. But with the ED scope I could actually see the corregated lines in the sign. That convinced me. Most high end scopes are $300-500 higher with ED or APO glass, so maybe the Celestron upgrade is only one lense or something.

 

[Gary in NH]

My question is simple, What is an ED lense??????

 

[Willyboy]

ED Glass

ED stands for "extra low dispersion" glass that gives better color correction and a sharper image. I think APO lenses provide color correction by using a more complex lens arrangement since some APO camera lenses use the ED glass.

 

[xring]

ED Glass

Gary , ED Glass is Extra-Low Dispersion Glass . When different Wavelengths of Light pass thru glass , they are bent at different Angles causing Chromatic aberration ......i.e. Color Fringing which some call a Rainbow halo . ED Glass , minimizes this . If you test Optics , your eye becomes sensitive to this , and once it does , it can bug you. Some seem to not notice it . If you are looking at some objects with lots of Colors ( like birds ) , ED Glass can be a real benefit .

 

[Hitman]

Another thing to remember that simply adding an ED element doesn't mean it is going to make a big improvement in a particular optic......

I am guessing that is the case with the Celestron. More of a marketing buzz word than a substantial improvement in the optics in that particular scope.

According to the website it "extra low dispersion glass" so I think they mean it is the entire light transmission path, not an element.

I was really surprised the tech did not point this out.

Thanks.