Is there really no way to eliminate the on camera flash for the OM-D?

Even if the flash is set to be a controller only (as opposed to master), the after-glow from the pre-flash can still impact the exposure for a macro type shot.  Blocking the controller flash is *the* solution everybody I know of uses to deal with this for macros (for non-macros, the after-glow is so weak it never matters.)  Just carry an index card in your camera bag.  An index card plus a rubber band is useful for various sorts of flash bouncing anyway.

Either that or use a radio, IR, or cable trigger.

Bart

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