Sony HVL-F56AM Flash - Work on APS-C Cameras?

[ebinrock]

This may be a stupid question, maybe not. I have a Sony HVL-F56AM Flash I bought on eBay for my Sony A300 A-mount APS-C camera. There's nothing in the flash's manual about it one way or the other, but do I need to go into a setting into the flash to make it recognize APS-C focal lengths? Because obviously 24-85mm in the 35mm sensor world is measured in different mm in the APS-C world. I know Nikon's flashes have a specific "DX" mode to switch them in, but I couldn't find out anything like that for the Sony. I just want to make sure the flash will, through TTL or ADI, accurately measure the focal lengths of my APS-C camera and lens, and see if there's anything I need to specifically set. Thank you, and this is my first post; thank you, moderator, for accepting me into the community!

 

[Angus Cameron]

• The HVL-F56AM is an A-mount system flash designed to communicate with the camera body.
• When the flash is set to Auto Zoom, the camera tells the flash what focal length the lens is at.
• On APS-C bodies like the A300, Sony/Minolta flashes use 35mm-equivalent focal length for zoom control.
• The camera automatically applies the crop factor internally before sending the info to the flash.

So the flash already “knows” it’s on an APS-C body — you don’t need to set anything manually.

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What you might notice (and why it’s normal)​

• The zoom display on the flash may show values like 24, 28, 35, 50, 85, 105mm
• These numbers are 35mm-equivalent coverage, not the actual lens focal length
• Example:
  • A 35mm lens on APS-C (~52mm equivalent)
  • The flash will zoom to around 50mm

This is correct behaviour and ensures proper light coverage.

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When you would change flash settings​

Only in these cases:

• Manual zoom mode → if you want wider or tighter flash spread for creative reasons
• Bounce flash → you may want to manually widen the zoom
• Using the wide diffuser panel → flash automatically switches to ~17mm coverage