[Leica] Genuine Fractals-any good?

[DouglasMSharp at netscape.net (Douglas M. Sharp)]

Frank Dernie schrieb:

> Hi Phong,
> I completely agree. Since film is the most digital of "analogue" 
> media, in that it consists of discrete grains, in a somewhat random 
> pattern, but still basically so many grains per square inch (depending 
> on film). When the film is exposed the grains are effected depending 
> on colour, light intensity etc but there are still a fixed number of 
> grains. When the negative is enlarged a new sheet of "analogue" 
> material is exposed in the enlarger. Unless this sheet of material has 
> identical grain pattern and number of grains as the original negative, 
> and the enlarger lens is perfect, the resulting enlargement has -must 
> have- interpolated information in it and is changed from the original.
> Frank
>
True enough but I think in the case of analogue/film/negative we should
get away from the term "interpolated".In the technical sense the definition
is that a new, narrower, grid is constructed from a grid of original
information. In the case of digital information the interstices between
the existing
value grid are "filled-out" with new values containing information from
the surrounding or neighbouring values.
The degree of influence (weighting) of the neighbouring real data on the
resulting value is governed by processing algorithms or simple matrix
filters. The simplest form would be to take an equal proportion of each
of the four corner values of a grid to produce a reasonable
approximation to what a real  value might be at the centre. More
complicated methods also take into account the neighbouring groups of
values, these can be overlapped or weighted (binning) to produce an
albeit less reliable but more realistic result including trends within
the data..

In the case of a negative or film the more or less random distribution
of grains shows no regular structure, the "data"  may  "look" different
after  enlargement
but the finite number of grains remains the same. An interpolation per
definition at source doesn't take place in so far that we are not
creating any new grains..
Douglas