The Speed Booster XL 0.64x is similar to the Blackmagic-specific 0.64x BMCC Speed Booster (MB_SPEF-BMCC-BM1), but has been completely re-designed to meet the following requirements:
The working distance has increased by 1mm to permit use on the Panasonic GH4 and a number of other Micro Four Thirds cameras without touching the flexible outer cover of the camera’s shutter mechanism.
The optics are optimised for a standard Micro Four Thirds filter stack thickness of 4mm rather than the 2.4mm found in Blackmagic cameras.
The image circle diameter has been increased to 21.63mm so that the full 17.3mm x 13mm Four Thirds format is covered. This has been achieved while maintaining unusually high image quality over the 17.4mm image circle used by the Panasonic GH4 in its Cinema 4k video mode.
Although the Speed Booster XL 0.64x has extra clearance compared to the 0.64x BMCC Speed Booster, there are still a number of Micro Four Thirds cameras that are not supported due to mechanical clearance issues. This is summarised in the table below, which is color-coded so that Green means the camera is supported and Red means the camera is not supported.
Note that many of the Red-coded cameras actually do function, but there is a minor interference with the protective shutter cover. Although slight contact with the shutter cover appears to have no effect on the functioning or cosmetics of either the camera or the Speed Booster we cannot support these combinations due to possible risk of damage.