Digital BW, The Print

john dean wrote:


> I'll tell you I just downloaded Stair Step Interpolation Pro 2 from
> the fred miranda dot com site and this software just gets better and
> better each version. For about $25 bucks you simply can't beat it.

The urls:

Win: http://www.fredmiranda.com/shopping/SIpro

Mac: http://www.fredmiranda.com/shopping/SImpro

Stair interpolation refers to iteratively computing a spline over and 
over again, usually in fixed proportions, until you get the output size 
you want. For example, if you used bicubic interpolation and increased 
the file size by 10% each time, until you got where you wanted to be, 
that would be stair interpolation. If you used S spline the same way, 
that would also be stair interpolation.

Several web sites report that FM SI Pro is bicubic stair interpolation 
at 12% per iteration, and several note that the results with "bicubic 
smoother" in CS2 is just as good. This sort of exchange is typical:

http://www.nikonians.org/dcforum/DCForumID36/2568.html#1

However, although there are several reports along these lines, I have no 
idea if they are true and I don't really know how you would test to see 
if the algorithm is bicubic. I'd really like to see a comparison between 
the FM tool, stair bicubic, and S spline. Does anyone want to exchange 
some files with me so that we can set it up?

Incidentally, S spline typically beats the snot out of stair bicubic, 
but then s spline costs $129 to Fred Miranda's $25, which isn't beans.

In unrelated news, there appears to be an entire web site devoted to the 
subject of interpolation of photographs, complete with discussion forums:

http://www.interpolatethis.com/

Also, Tyler, thanks very much for pointing out the discussion on the 
epson wide list - it was very illuminating.

-- 
Jeff Medkeff
Eagle River, Alaska