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Old 06-08-2018, 05:07 PM
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Peter Ward
Galaxy hitchhiking guide

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Sigma 105mm F1.4 Art

OK you can blame the rain on me....new toy arrived late last week,

A short review can be found here
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Old 07-08-2018, 04:00 AM
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skysurfer
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105mm / 1.4 = 75mm aperture.

You can test it by flashlight test by shining through the viewfinder's eyepiece and measure the image circle coming from the lens (i.e. the reverse direction of the 'normal' light path).
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Old 07-08-2018, 05:59 AM
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Peter Ward
Galaxy hitchhiking guide

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Quote:
Originally Posted by skysurfer View Post
105mm / 1.4 = 75mm aperture.

You can test it by flashlight test by shining through the viewfinder's eyepiece and measure the image circle coming from the lens (i.e. the reverse direction of the 'normal' light path).
I ran a micrometer across the objective..

It measures 90mm in diameter..with a new picture now on the relevant web page.

Optical vs physical sizes can easily vary with multiple elements behind an objective.

Last edited by Peter Ward; 07-08-2018 at 12:35 PM. Reason: correction
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