Zhong Yi Optics has announced a B4 to M4/3 2X extender. This allows you to run 2/3″ B4 broadcast lenses on any camera that has a M4/3 sized sensor, such as a Panasonic GH5 or BMPCC4K.
The Zhong Yi Optics B4 to M4/3 2X Extender uses an optical lens that doubles the focal length os the attached B4 lens to cover the M4/3 sensor size. The extender’s optical configuration consists of 8 elements in 5 groups.
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What you clearly need to be aware of with a product like this is that you need to be able to externally power a 2/3″ B4 broadcast lens to use the servo functionality. It is also important to note that a lot of the older 2/3″ B4 lenses were designed for use on 3CCD sensors and they may not look particularly good on CMOS sensor cameras.
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The end of the extender that attaches to the lens is made out of aluminum alloy, and the other end hat attaches to a camera is made out of stainless steel.
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The extender features a tripod mount that that is compatible with the Arca-Swiss standard.
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Other options
This is not the first B4 to M4/3 adapter. Other options have been available for years. Here are some of them:
You need to be aware that some adapters are a lot better than others.
Price & Availability
The Zhong Yi Optics B4 to M4/3 2X Extender retails for ¥ 99,000 (around $940 USD).