Digital BW, The Print

--- In DigitalBlackandWhiteThePrint@yahoogroups.com, "Paul Roark"
<paul.roark@v...> wrote:
>
> Very interesting, but it also sounds very complex and expensive.

Yup. Just like all digital cameras were, 15 years ago. Give plenoptics
another decade. and it will be mainsteam.

> I assume most of us are using multiple-frame zone-focusing now to
increase
> DOF.  I've been rather surprised that some enterprising software
writer has
> not made a program that can automatically combine the multiple frames of
> these current-technology shots.  Conceptually, it's an easy thing to
do.  

Actually, it' pretty dang hard. A lot of frequency domain math and
interpolation. Just the decision logic for layer selection has been
the topic of dozens of excellent papers and a few Ph.D. theses. But
that hasn't stopped many people from doing it. The technique is
commonly referred to as "focus stacking".

The program that I use most often for this is Mr. Hadley's amazing bit
of freeware called "CombineZ". It takes a bit of learning, but has
outstanding results.

http://www.hadleyweb.pwp.blueyonder.co.uk/index.htm

"Helicon Focus" is an excellent (and affordable) commercial image
stacking product, and if you get the "pro" version, it comes bundled
with the (also excellent) noise removal tool "Helicon Filter". I don't
think it's as powerful as CombineZ, but it is "drag and drop" easy.

http://helicon.com.ua/pages/

Been meaning to check out a couple of other tools:

Syncroscopy Auto-Montage

http://www.syncroscopy.com/syncroscopy/automontageshort.asp

And Acclaim "Focus Magic", which is a single image blind deconvolver,
not a stacker, but can tell you some pretty interesting things about
what went wrong with an image and how to shoot it better next time
(not that Acclaim things that the right way to use their software,
mind you).

http://www.focusmagic.com/

And, here's an excellent article about stacking workflows, which also
has a good comparison of CombineZ and Helicon Focus.

http://www.outbackphoto.com/workflow/wf_72/essay.html

And three of my favorite focus stacks, two cactus flowers and a
spider. All are macros at between 4x and 10x magnification, DOF is
under 0.5mm, so stacking was necessary to get the DOF up into the
2-4mm range of these pictures.

http://www.swissarmyfork.com/images/2004-01-24-0086-stack.jpg
http://www.swissarmyfork.com/images/2005-01-16-0004-stack.jpg
http://www.swissarmyfork.com/images/2005-05-07-0010-stack.jpg

Ciao!

Joe