• 54 guide number
• Variety of auto flash functions, including P-TTL
• Automatically adjusts discharge angle to focal length on select lenses
• Auto power-off function; 100-degree verticle and 180-degree horizontal adjustable angles
• Clip-on style auto-zoom flash attachment

Large guide number
Despite its compact dimensions and clip-on design, the AF540FGZ auto flash offers a large guide number of 54 (at ISO100/m) to accommodate a wide range of flash applications.

Advanced auto flash functions
The AF540FGZ features a variety of flash functions, including advanced P-TTL auto flash in which a pre-emission from its spotbeam projector is detected by the camera's light sensor to accurately control the main discharge level needed for proper illumination of the subject. Other functions include TTL auto flash, auto flash, manual flash, high-speed synchronization and wireless P-TTL.

Auto discharge-angle adjustment
When mounted on a Pentax autofocus SLR (after the Z-10 and including digital-format models) equipped with an FA-, FA J-, DFA- or DA- series lens, the AF540FGZ automatically adjusts its angle of discharge to the lens' focal length (automatic function may not be available for certain combinations of a camera body and a lens).

Other Features

• "Digital" position newly provided on the focal-length conversion scale of the zoom head to accommodate digital SLRs.
• Bounce flash function, with adjustable angles of -10 to 90 degrees vertically and up to 180 degrees horizontally.
• Power-zoom flash head to cover angles of view for 24mm to 85mm lenses (in 35mm format).
• Built-in wide-angle panel that slides out to cover 20mm angle of view (in 35mm format).
• Built-in catch-light panel, which is useful and effective in portrait photography
• External power supply with the optional TR Power Pack II.
• Battery-saving auto power-off function (user cancellation possible).