I don't think it has it, and quick review of the manual (I don't have
the camera) doesn't mention it. (Is there a "ME" position on the right
hand lower dial ... that would be it).
One way would be, in a darkened setting, dark background, to shoot bulb
with the RC cable (locked open) and flash exposure (incident metered).
While setting up between two shots, the viewfinder will be dark however,
making it quite difficult to frame and focus.
The PShop route will be easier.
I don't know if other digitals can to proper mutiple exposures.
Yes. Use of a dark background in shots still helps, put your images in
layers and then adjust as needed.
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