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Sony HVL-F20S review: Sony HVL-F20S

Name: Sony HVL-F20S
Brand: Sony

The F20S is a more powerful alternative to the bundled flash that comes with NEX cameras. Provided you don't need on-board dials and buttons to adjust its intensity, this external flash should suit most needs.

Lexy Savvides Principal Video Producer

Lexy is an on-air presenter and award-winning producer who covers consumer tech, including the latest smartphones, wearables and emerging trends like assistive robotics. She's won two Gold Telly Awards for her video series Beta Test. Prior to her career at CNET, she was a magazine editor, radio announcer and DJ. Lexy is based in San Francisco.

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Lexy Savvides

Feb. 13, 2012 1:40 p.m. PT

3 min read

For those photographers ready to flash, we salute you. Flash with an extra burst of light, that is. The HVL-F20S is an external flash unit that is compatible with any of the NEX cameras — with the exception of the NEX-7. It's bigger and much more powerful than the included clip-on flash for the NEX cameras. It sits in the proprietary hotshoe mount, drawing power from the camera itself rather than via any batteries of its own. Sony claims it reduces the overall battery life of the camera (according to its CIPA rating) by around 20 per cent when in use. For example, the battery life of the NEX-C3 would be reduced to 320 shots rather than 400 shots when the flash is in use.

8.0

Sony HVL-F20S

The Good

Much more powerful than the bundled NEX flash. Provides a decent amount of light.

The Bad

Flash unit can't swivel. No external controls.

The Bottom Line

The F20S screws into place with a small, rotating dial at its base. There's only one shooting angle to choose from, tilted up 75 degrees. Another unfortunate design issue is that the flash unit doesn't swivel around its base to give directional light. It can be bounced upwards by rotating the ring on its side for bounce flash. Also provided in the box is a small wide converter attachment that clips on the front of the flash unit to broaden how far the light is thrown.

There's no external dials on the F20S to adjust anything, including power or flash intensity. Controlling the flash compensation has to be done through the camera menus, and turning the flash on and off is done by raising and lowering the head.

Sony doesn't recommend the use of Alpha lenses with this flash unit, attached via the E-mount to A-mount adapter. We didn't have any Alpha lenses to test this, but Sony claims the larger lenses can block the flash throw, darkening the lower part of the image.

Performance

We coupled the flash unit with the NEX-5N and the 16mm f/2.8 pancake lens. As would be expected with such a wide lens, there was a lot of light falloff towards the edges of the frame with some vignetting occurring.

As noted earlier, the flash has no ability to rotate to bounce the light depending on the shooting configuration. So, don't expect to be able to take successful photos in portrait orientation with the F20S.

A comparison between the different flash configurations.
(Credit: CBSi)

With the built-in diffuser tilted over the flash unit (for shooting at standard focal lengths), we did notice the pattern of the plastic that the light passed through appeared on the wall behind our test subjects. It's not a serious issue and could be alleviated by moving a subject further away from the wall, but worth noting nonetheless.

The flash doesn't cause any noticeable colour casts or pronounced shadows, making it ideal for portrait work. We'd suggest using a slightly longer lens than the 16mm, though.