This 0.8x focal reducer speed booster is upgraded from the 0.71x version. For example: Mamiya645 80mm/F1.9 lens to Hasselblad X2D. 0.8x Optics speed booster. With this adapter, the lens will fit physically, but automatic diaphragm, auto-focusing, and other auto functions will not work, only manual model will be available.It's a locking version adapter.
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