August 29, 2014, 05:59:28 AM

Author Topic: 5D3 Microfocus Adjustment  (Read 1157 times)

clifton425

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5D3 Microfocus Adjustment
« on: October 07, 2012, 12:13:46 PM »
With the 5D3 having separate MFA's for both the long and short end for each lens, I'm curious as to what the camera does with intermediate focal lengths. Does the camera apply a linear change between the extremes or simply switch from one to the other at some intermediate focal length?

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5D3 Microfocus Adjustment
« on: October 07, 2012, 12:13:46 PM »

Mt Spokane Photography

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Re: 5D3 Microfocus Adjustment
« Reply #1 on: October 07, 2012, 12:44:42 PM »
It interpolates the value. 
Previously discussed here
http://www.canonrumors.com/forum/index.php?topic=6229.msg117082#msg117082

neuroanatomist

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Re: 5D3 Microfocus Adjustment
« Reply #2 on: October 07, 2012, 12:56:38 PM »
Correct - a simple integer linear regression between the two values across the focal range of the lens.  For the plot below (with the 1D X, but the 5DIII is the same) each lens was set to W = -10 and T = +10.

EOS 1D X, EOS M, and lots of lenses
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Re: 5D3 Microfocus Adjustment
« Reply #2 on: October 07, 2012, 12:56:38 PM »