Video B4 (2/3" and 1/2") lens to Micro four-thirds mount adapters

cults3d

This is a two-part adapter that attaches securely to the existing B4 flange on the lens and offers a parfocal mount for M4/3rds (Lumix, BMPCC etc). It's not designed to support a B4 lens via the M4/3 mount since they are mostly too heavy, but the adapter will easily hold small DSLRs via the lens. The clamp requires six M2.5x12mm screw/bolts and lock nuts for the captive nut recesses. When clamped together, the two parts ensure a tight grip on the B4 flange, so don't overtighten; a deliberate gap has been left to allow adjustment of the pressure around the mount (any over tightening will be apparent by squashing the gap). Parfocal adjustment is assumed to be on the lens (such as Canon J9ax5.2B4 or Canon J15ax8B4), where there is 1mm of adjustment, and this adapter should place the lens in the center of the 1mm adjustment range. The latest addition includes an adapter for ½" video lenses like the Canon H15sx6, which use a similar "B4" bayonet but have a shorter flange distance of 12.26mm. ½" bayonet flanges can be identified by their slightly larger (3.4mm dia) locking pin.