baffling question for anyone who knows

[Hal Watkins]

I work with a small team of researchers studying dragon fly aspects. We use
small, mostly higher end, consumer camcorders to capture the flies in
flight, mating, eating and whatever else comes up. Lately, we have been
trying to study slow motion movement of the wings (much like slo mo
hummingbird studies). However, we have been running into a problem. We are
trying to record at the max of our camcorder, 60 fps, and then slow that
down. The result is fantastic but only if we ":macro" the fly at 30" away
(which allows the fly to almost fill the camcorder screen). If we try and
record the flies up close, say 4" away, and still have plenty of light, the
wings often appear steady or move in erratic ways. We can't figure out why
when the wings are recorded and slowed down from a distance, they appear
fine, but when recorded up close, they have non-movement or distortion.
Does anyone here know and have a solution? We'd like to get some flies up
close (without using the macro setting), but so far the erratic or
stationary wing phenomenon has eluded us. Please help.

Thanks in advance,
Hal Watkins

[Smarty]

Hal Watkins wrote:

I am a bit confused about your settings, Hal. In the first case things
work well at 30", when you "macro", but they do not work well at close
settings such as 4" when you are 'not' using macro?

It might be best to name the camera and lens you are using, the details
of your camera settings for the two cases, and what you are failing to
accomplish. My impression is that you need / want more close up /
detailed views of the wings, but getting closer spoils the capture.
Have you changed the camera settings between the 30" and 4" examples?

Please clarify and perhaps one of us can give you some further
assistance. As you might imagine, most consumer cameras have a lot of
automation, and perhaps some camera setting is being changed without
your knowledge as a result of different lighting, focusing distance,
etc.?

[ergomatic]

Hal,

I think you might be seeing a strobe effect, or something related to
the refresh rate of the ccd in the camera. It also occurs to me that
60fps is really quite slow for doing motion studies; I would want at
least 200fps to look at this kind of motion. Have you looked at the
Casio Exilim series:
http://exilim.casio.com/products_exf1.shtml
...even the cheap ones can do 1000fps at reduced resolution. Also,
http://www.alliedvisiontec.com/us/products/cameras/gigabit-ethernet/prosilica-ge/ge680.html
can do 200 fps and uses GigE interface, pretty cool.