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05-18-2009, 05:19 AM   #16
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Location: Cork, Ireland
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So I have been doing some more thinking and also calculations:

If I had a 200 DA* and was roughly 500M from where I wanted to focus:
F1 Car @ 200KM/Hour
= 3.33KM/Minute
= 0.056KM/Second
= 56M/Second
or 1 metre in 0.093 a second

My DOF if I set the 200:
to F8 = 20.74M
to F16 = 47.36M

Which leaves me a reaction time all things being perfect of 0.19 Seconds @ F8 or 0.44 Seconds @ F16
Are my calculations correct?

And does that mean I would be better off with a DA*50-135 instead?

Last edited by robbiec; 05-18-2009 at 05:28 AM.

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