[Leica] Janin Acres - Sony stitch

[roark.paul at gmail.com (Paul Roark)]

Adam,

I found that every geometric alteration of a file destroys information -
softens the details.  That includes perspective correction, stitching and
stacking, where the files have to be altered to fit together properly.  I
also found that if the files were increased in size 200% using one of the
"smarter" re-sizing programs, more of the detail could be retained when a
subsequent stitching or other geometric alteration was done.

A comparison in a different stitching example is shown at
http://www.paulroark.com/BW-Info/Perfect-Resize-comparison.jpg .  There I
used "Perfect Resize" which was what onOne software re-named "Genuine
Fractals" when they bought it.  Until PS CC's new resizing algorithm came
out, Genuine Fractals was the best at preserving detail.

In the example noted above, the top left image shows, at 100%, the top of a
building in a Chicago image when no size increase was done first.  The
image just below shows the stitch result when the files were increased 200%
first.  To the right is the original image, unaltered.   (The final image
is at http://www.paulroark.com/Chicago-River.html .)

I use 200% because I think the resulting file will have mostly left the
original pixels as is and added new pixels between them.  I have not tested
this, but it seems to work well.  (I don't pretend to understand all the
math behind these interpolation methods, and I'd guess Adobe and others are
not about to explain too much about what they are doing.  I just look at
the results and go with what seems to work the best.)

It appeared to me quite some time ago that Genuine Fractals was able to, in
effect, preserve straight lines better than the bicubic interpolation in
PS.  The latest PS CC has taken the math one step further by using
algorithms that determine which areas should be smooth.  Of course all of
these are mathematical good guesses, but the bottom line results show why
the software and camera companies are integrating them into their various
processing approaches.  As a practical matter, these "smart" re-sizing
programs are able to increase the apparent if not real signal to noise
ratio in files.

I hope this is somewhat responsive to the question.

Paul
www.PaulRoark.com