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Old 14th December 2017
Petrochemist Petrochemist is offline
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Re: Laowa MSC Magic Shift Converter

Quote:
Originally Posted by Harold Gough View Post
Not a TC. It doesn't affect the FL. More like one of those speed reducers. As it spreads the whole image circle, unlike just the inner part with a TC, it must need one stop more exposure, just as with a x1.4 TC.

Harold
I'd have to disagree with you there. The focal length does change (as it does with focal reducers but in the opposite direction).


It can't create imaging light from nowhere. It spreads the image just as a TC does, the difference being the extra image circle is not blocked by baffles & the mount is designed to move to make use of the larger circle.


If you re-read the second article you linked too you should see:
'converts the Laowa 12mm f/2.8 Zero-D to a 17mm f/4 lens with +/- 10mm Shift capability without any vignetting'
12mm to 17mm looks like a change in focal length much the same as produced by a 1.4x TC & the 1 stop change is entirely consistent with that.
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