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60mm versus 65mm objective lens

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tpcollins View Drop Down
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    Posted: January/17/2009 at 15:36

I'm anxiously waiting for my 15-45x65 Stokes Sandpiper to arrive and I stumbled across  a Konus ad for the same size claiming the 65mm objective had 17% more light gathering capability than a 60mm lens. I thought that was a bit high since the 65 is only 8% larger, then I thought maybe that's the twilight factor. So I did the math between the two using 15 power and the difference is 16 versus 18.77 and the increase is 17% - duh.

I know the best low light binocular for spotting game out west is the 8x56 because of the twilight factor of 49. Am I really going to see a difference of 18.77 over the 16? Thanks.

  

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lucytuma View Drop Down
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Post Options Post Options   Thanks (0) Thanks(0)   Quote lucytuma Quote  Post ReplyReply Direct Link To This Post Posted: January/17/2009 at 17:46

Shouldn't make a huge difference, if any at all.

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lucznik View Drop Down
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Post Options Post Options   Thanks (0) Thanks(0)   Quote lucznik Quote  Post ReplyReply Direct Link To This Post Posted: January/17/2009 at 20:28
Originally posted by tpcollins tpcollins wrote:

I'm anxiously waiting for my 15-45x65 Stokes Sandpiper to arrive and I stumbled across  a Konus ad for the same size claiming the 65mm objective had 17% more light gathering capability than a 60mm lens. I thought that was a bit high since the 65 is only 8% larger, then I thought maybe that's the twilight factor. So I did the math between the two using 15 power and the difference is 16 versus 18.77 and the increase is 17% - duh.

I know the best low light binocular for spotting game out west is the 8x56 because of the twilight factor of 49. Am I really going to see a difference of 18.77 over the 16? Thanks.

 
Yes you will "see" the difference.  The math doesn't lie and 17% is significant enough to notice.  Though the difference will really only be seen in comparisons to other, like-quality spotting scopes.
 
So, will your 65mm Stokes Sandpiper be brighter than say, a 60mm Nikon Fieldscope at the same powers?   Probably not.  The Nikon will undoubtedly employ better glass, superior coatings, etc. that will allow it to overcome the smaller size of their objectives.
What if the hokey pokey really is what it's all about?
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