The Sony HVL-F20M External Flash is an on-camera flash that
supports the use of the Sony Alpha TTL system and is compatible with
Sony's Multi Interface shoe. When compared to the built-in pop-up flash
of many cameras, this flash helps to extend the effective flash working
distance by providing a guide number of 65.6' / 20m at ISO 100.
Additionally, this flash can serve as a wireless controller for
triggering an off-camera flash.
For controlling the flash exposure the Advanced Distance Integration
(ADI) flash metering system works in collaboration with Alpha cameras
and lenses that feature an integrated distance encoder to intelligently
produce balanced results. By accounting for the subject-to-camera
distance, as well as ambient light and subject reflectivity, the ADI
system works to control the flash output in order to provide precise,
consistent flash exposures.
A built-in diffuser helps to control the spread of the flash; when
enabled the spread is wider to suit working with wide-angle lenses, and
when disabled the flash beam is narrower and longer to benefit working
with telephoto lenses. Additionally, the head can tilt between 0-75° for
bounce applications and greater control over the direction of the
The HVL-F20M provides a guide no. of 65.6' / 20m (ISO 100),
which effectively extends the flash range beyond that of a built-in
The Multi Interface shoe connection enables expanded
compatibility with Sony Alpha cameras in addition to other cameras
featuring a traditional hot shoe.
Accurate TTL flash metering is possible when used with
compatible Alpha cameras and lenses that incorporate a distance encoder.
The Advanced Distance Integration (ADI) flash metering system works to
produce both exposure and white balance compensation regardless of
background conditions. By measuring the subject to camera distance,
ambient lighting, and pre-flash reflectivity of the subject, the ADI
system intelligently calculates an effective guide number in order to
control TTL metering.
When attached to a compatible camera, this flash can be used as a
wireless controller to remotely trigger an off-camera flash.
The flash head is able to bounce upward to +75° in order to
provide greater control over the direction and spread of the flash
A built-in diffuser helps to spread the light out over a wider
range to better suit shooting with wide-angle lenses. Additionally, a
tele setting enables a longer flash throw with a narrower beam in order
to benefit working with longer, telephoto lenses.
Intuitive use is afforded through the automatic on/off function
by simply raising the flash into shooting position. An easily accessible
switch on the side of the flash permits quick switching between direct
and bounce flash modes, and a charging lamp indicates when the flash is
ready for use. The flash utilizes two AAA batteries as its power source
and provides over 90 flashes when using new alkaline batteries.