Arri PL is a lens mount developed by Arri for use with both 16 mm and 35 mm movie cameras. The PL stands for "positive lock". It is the successor mount to the Arri bayonet; however, unlike the bayonet mount, it is incompatible with older Arri-mount lenses, due to the larger diameter.
The mount contains four pronged flanges which each contain a notch towards the center. Any of these four notches can be used to align the mount to a locating pin located approximately 45 degrees clockwise from the top of the camera's lens mount.
Flange focal distance: 52.00 mm (51.97 mm for the Arri SR high speed models)
Diameter: 54.00 mm (62.00 mm for Arriflex 765, that mount is known as "Maxi PL-mount")
- 35 mm: Arriflex 35III (later models), Arriflex 35BL3 (later models), Arriflex 35BL4, Arriflex 35BL4S, Arriflex 535, Arriflex 535B, Arriflex 435, Arriflex 435ES, Arriflex 435 Advanced, Arriflex 435 Xtreme, Arricam ST, Arricam LT, Cinema Products FX35, Moviecam SuperAmerica, Moviecam Compact, Moviecam SL, Aaton 35
- 16 mm: Arriflex 16SR2 (later models), Arriflex 16SR3, Arriflex 16SR3 Advanced, Arriflex 416, Aaton XTRplus (standard), Aaton XTRprod (standard)
- 65 mm: Arriflex 765
- Digital: Arri Alexa, Arriflex D-20, Arriflex D-21, Dalsa Origin, Dalsa Origin II, Sony F35, Sony F65, Phantom, Canon C300 PL
Material from http://en.wikipedia.org/wiki/Arri_PL
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