Are there special settings to use a "regular" external flash? I have a Canon Speedlite 430ex II flash from a previous camera, and when I try to shoot with it, it fires fine (so, it is in the shoe far enough), but completely overexposes everything. I was hoping "auto" mode would just work, but clearly I'm missing something.

Some setting of "the flash plugged in is way stronger than the dinky little pop-up flash, react accordingly"?


2 Answers 2


The good news is your camera and flash work together in sync. This is thanks to ISO standards about hotshoe dimensions and electronic communication.

The bad news is your camera, other than telling the flash when to fire, can't communicate with your flash.

The Sony multi-interface hotshoe has all the contacts for communicating with a Sony HLV flash at the back of the the hotshoe, where the edge of the flash's foot would be. Your Canon 430EXII doesn't have any contacts there. It's using four other pins on the face of the foot. Where the RX10 has no contacts.

The sync pin is the one in the middle (where the hotshoe of the camera is), and ground is the rails and those side-contacts above the foot on the flash. That's why the sync signal gets through. But without the other signals, the flash is firing at full power all the time.

You have to put the 430EXII into M mode, and then explicitly set the power level you want, using the flash's controls and LCD display. And to know which power level to use, you either have to be good with guide numbers, or willing to shoot a test shot, chimp, adjust, and reshoot to figure it out. I tend to start at 1/4 power as the "happy medium" and adjust accordingly.

footnote: if you had a 580EXII/600EX-RT/600EX-RT II, the external sensor could be used to automate power setting by putting the flash into Auto.M mode, and then feeding in the iso and aperture settings being used. Also, if you had a high-end Nikon flash (SB-800/900/910), you could use Auto mode in a similar manner. Autothyristors can still be useful.

If you really want a full function flash with TTL/HSS and all the bells and whistles, you may want to blow the bucks on a different flash that speaks the Sony flash protocol with a multi-interface foot.


This is to be expected. Without proprietary communication, the camera doesn't know anything like what you suggest with the flash plugged in is way stronger than the dinky little pop-up flash, react accordingly. You will be best off operating your camera in the M exposure mode with fixed settings, and correspondingly changing the power of the Canon flash manually in its manual mode.

This sounds intimidating, but it's not really that hard. For typical indoors, I suggest starting at a shutter speed of ¹⁄₁₆₀th or so, ISO 400, and aperture f/5.6. Take a test shot, and adjust the flash power up or down to suit. You probably want the flash to be at about half power (for faster recharge and less overheating), so you can also change the ISO and aperture as necessary.

Changing the shutter speed won't affect the exposure, unless you make it long enough that the ambient light comes into play. Usually, it's just the short flash burst. Your camera has a somewhat unique advantage, in that it can sync even at the fastest shutter speeds, which is pretty nifty if you are trying to kill the ambient and take flash photos in broad daylight.

But, in any case, if you don't want to deal with any of that, I'd suggest trading it in for a Sony-specific flash.


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