I was standing outside the new library of alexandria the other day, looking at a sun dial.
and I thought it would be cool to overlay multiple exposures.
But it doesn't appear to be possible with a digital. At least not as such.
There are probably techniques in photoshop or the like to layer images.
But I would love to be able to select an image on my camera and "lock' it and then take
another exposure over it.
That should be possible.
Digital would be even better than film, because with film you would have to do multiple exposures
one after the other.
With digital you could go back to photo N.
Does that make sense?
PS Layers
http://www.naturephotographers.net/articles0903/tg0903-1.html
I used to fiddle with double exposures using film (depress the rewind release button and advance the shutter) but using layers is really the way to go.
--Terry