> Accurate frame positioning may be done perhaps with the sprocket hole count
> or something, but I can not immediately figure out how the camera can
> "remember" the frame number of the particular film which was changed mid
> roll. If it could, it may have something to do with the data imprint but it
> is not of magnetic memory type. So, I am not quite sure about this
> AUTOMATIC return to the frame when the film was changed mid roll. There is
> no point in speculating but I am just curious and perhaps someone with
> better brain could give me a hint or two for me to play with while waiting
> for the full spec :-)
I was wondering the same thing... I can't see any way to identify a specific
film, or to detect which frames have been imprinted. Unless the exposure of
the imprint changes the electrostatic signature of the media significantly
or something, but that seems unlikely.
I guess it could 'remember' frame number for one film, so as to allow you
to alternate between two. Or, given DX coding, it could remember frame
numbers for several, as long as they all were different ASA on each one.
Actually, the DX code not only identifies ASA but also number of exposures
and exposure latitude. But it still would not identify transparency vs
negative of the same ASA, or colour vs black and white.
Maybe it punches a hole between frames that it can detect later, or something.
Just guessing really.
- Peter
-
This message is from the Pentax-Discuss Mail List. To unsubscribe,
go to http://www.pdml.net and follow the directions. Don't forget to
visit the Pentax Users' Gallery at http://pug.komkon.org .
