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Videography

> From: Bjorn Straube <straube at digital_net>

> Hi all,
>   The thread on photography got me to thinking about useing video
> camcorders.  If one has a video card, pictures can be directly down
> loaded into photo shop and then the sky's the limit.  Has any one tried
> this? 

Yes.  And no.  While video does produce "visible" results, they are not
what I'd call stellar.  I should probably add something about this to the
Krib where I already compare quality of Photo-CD and flatbed scanning. The
difference between a video scan and a flatbed scan off a print is
striking.  (Incidentally, video captured to a card is about the same
quality as one of those consumer-end digital cameras... I suspect they use
similar technology.)  The colors are much more washed out and tend to look
"pinkish", the resolution is effectively 320x200 (once you de-interlace),
and of course, you can't take flash pictures.

For some examples, compare for instance :)

  www.cco.caltech.edu/~aquaria/Krib/Apisto/Mystery/
    with
  www.cco.caltech.edu/~aquaria/Krib/Apisto/A-nijsseni.html

The former are some video snaps and the latter scanned photo-CD's.
I also put one of Steve Pushak's Echinodorus snaps up (in the Echinodorus
section, natch! ...Krib/Plants/Plants/Echinodorus.html).

I personally DO use the camcorder method, for two specific instances:

   1. Publication in our local aquarium society bulletin, because the
resolution of the printing is such that a video snap makes a reasonable
1.5" x 2" printed picture.  It's also nice, because as the deadline
approacheth, I can get something out real quick.

   2. For quick purposes only... such as that apisto page cited above.  I
think I've put up a "Help, what's this plant?" query once.  Sure nice for
fast turnaround. 

   3. I can actually get closer-up with my video camera than with my macro
lens on my 35mm!  Some of the best "fry" shots I have are from video.


A couple tips for scanning from video:

  1. Interlacing: Because each video frame of 525 lines is really TWO
fields of 262 lines alternating every 1/60 second and offset by 1 line,
when you capture something that moves, it looks very silly, kind of like
it's been torn apart into two ghosts.  The solution is either to capture a
still portion of the video, or use a de-interlace filter, which removes
the odd or even lines (and halving your resolution).

  2. Go close-up.  Don't bother trying to get any background in the
picture.  Use up as much of that resolution as you can.  Steve's picture
works because the sword takes up the whole picture.  If he'd backed off in
the least, you wouldn't have been able to distinguish the plant from the
gravel.

  3. Go for good saturation, brightness, etc.  I guess this is applicable
to scanning in general, but it's fresh in my mind from some scans I got
for our club pub this month.  They were all way too dark.  I was able to
lighten them, but it sure makes the picture noisy.

Well, a bit long.  Hopefully a bit helpful.

   - Erik

---
Erik D.. Olson					         amazingly, at home
eriko at wrq_com