Compact and very capable, the VC-310SMI Compact On-Camera TTL Flash from Bolt is fully compatible with Sony's ADI / P-TTL system (except for a7 III, a7 IV, a7R III, a9, a9 II, a6100, a6400, a6600 and RX1R series) and offers a plethora of features for advanced on- and off-camera flash photography. The relatively small unit has a guide number of 105' at ISO 100 for easily illuminating a range of subjects as well as coverage for 28mm lenses on full frame cameras or 18mm on APS-C cameras. The included diffuser can soften the output of the flash while increasing the coverage to 17mm on full frame or 12mm on APS-C. For bounce capabilities the VC-310SMI can tilt from -7 to 90° and rotate left 60° and right 90° for more flattering lighting than provided by direct flash.
Another feature of the VC-310SMI is the ability to use LED lights to preview lighting and as a focus assist. This model can be used as an optical slave in manual mode and a stroboscopic mode is available for creative effects requiring multiple flashes during a single exposure for numerous possibilities. The ability to accept firmware updates via a Micro-USB port ensures compatibility in the rapidly changing digital landscape. This flash comes equipped with the Sony Multi Interface Shoe and is not directly compatible with older cameras using the Sony/Minolta Auto-lock Accessory Shoe. Optional adapters are available for using this flash with older cameras.