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    Hawke Frontier ED 8x36: another 36mm Chinese ED

    I knew that Wolfram|Alpha could do this kind of thing, and more. I'm rather surprised they haven't been bought out by Google or M$. But I suppose if Google can do the basics itself, why spend billions buying Wolfram|Alpha?
  2. S

    Hawke Frontier ED 8x36: another 36mm Chinese ED

    I suspect we could both agree to settle at 8 degrees ;) I learned something from all this; I hadn't realised Google would do trig functions. I hadn't even realised Google would recognise "pi". Clever stuff.
  3. S

    Hawke Frontier ED 8x36: another 36mm Chinese ED

    I'm way out of my depth here, but shouldn't it be: 2*arctan(210/3000) = 8.00834588 degrees? Not that this degree of implied accuracy is appropriate. Just noticed - you did say "roughly". You are clearly ahead of me. I leave this post just in case anyone else is interested in the maths. I...
  4. S

    Hawke Frontier ED 8x36: another 36mm Chinese ED

    Agree that one is clearly wrong. I was curious as to how the discrepancy might have arisen, so I crunched some numbers. Suppose, as Kevin suggests, the latter - 140m@1km(=1000m) - is correct. If we were to convert 140m to feet we get 459 feet. But what Hawke appear to have failed to do is...
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