Interfit S1 AC/DC HSS TTL Monolight

The Interfit S1 AC/DC HSS TTL Monolight is a 500Ws battery- and AC-powered monolight built for photographers who want studio-quality output in both on-location and studio settings without being tied to a single power source. It combines a removable lithium-ion battery and a multi-voltage AC power pack into one complete package, positioning it as a versatile, high-powered lighting solution for photographers who move between locations and fixed studio setups.

At the core of the S1 is 500Ws of flash power delivered through Interfit’s IGBT technology, supporting flash durations as short as 1/9000 sec for freezing fast action while maintaining a steady, color-accurate 5700K color temperature (±100K) throughout the entire power range, minimizing color correction time in post-production. The unit offers three shooting modes: Wireless TTL (for Canon, Nikon, or Sony, with a dedicated camera-mounted transmitter sold separately), full Manual mode, and High-Speed Sync up to 1/8000 sec, which uses the flash’s top four power levels (62.5 to 500Ws) to allow wider apertures or overpowering bright ambient light. In TTL mode, the camera’s metering automatically adjusts power output across a broad 9-stop range, with +/- 3 stops of exposure compensation adjustable in 1/3-stop increments for fine-tuning.

Power comes from an internal, removable 4500mAh lithium-ion battery rated for up to 350 full-power flashes (or over 400 in High-Speed Sync mode), recharging to full in about 3 hours via the included charger. Because the unit is AC/DC, it can also run directly from a wall outlet using the included multi-voltage AC power pack while the battery charges, giving photographers uninterrupted studio use regardless of location voltage. Wireless control is available at distances up to 328 feet, with three individually controllable groups for creating dynamic multi-light ratios across a working range of up to 300 feet.

The unit includes a built-in LED modeling lamp for previewing light direction and quality before firing, along with a mini-USB port for connecting to a computer and installing firmware updates to maintain compatibility with camera systems over time. Build quality includes a 7″ Bowens S-Type reflector included as standard, and the S1 uses the widely compatible Bowens mount system for softboxes, umbrellas, and other modifiers.

Key Features
– 500Ws AC/DC battery- and mains-powered monolight
– Wireless TTL (Canon/Nikon/Sony via optional transmitter), Manual, and High-Speed Sync modes
– High-Speed Sync up to 1/8000 sec
– IGBT technology; flash durations as short as 1/9000 sec
– Consistent 5700K (±100K) color temperature across power range
– 9-stop power range with 1/3-stop TTL exposure compensation (+/- 3 stops)
– Removable 4500mAh Li-Ion battery (up to 350 full-power flashes; 400+ in HSS)
– Included multi-voltage AC power pack
– Wireless control range up to 328′; 3-group control up to 300′
– Built-in LED modeling lamp
– USB port for firmware updates
– Includes 7″ Bowens S-Type reflector
– Bowens-mount modifier compatibility