Mark C wrote:
I did that and will put together the results. I saw falloff between
shutter speeds - 1/45, 1/90, and 1/180 had more pronounced banding that
1/60 and 1/125. But all those speeds had some banding. All speeds <1/45
showed no banding and all > 1/180 showed about the same degree of
banding. I'll label the images and put them into a single file.
Very cool. This was with the electronic shutter if I recall correctly?
Did the number of bands change with different shutter speeds? I'm
wondering if the length of time to expose the full sensor changes, and
they just expose each row for different amounts of time.
Did you get different results with electronic versus mechanical shutters?
Mark
On 3/2/2017 4:26 PM, Larry Colen wrote:
<signal processing geek>
Mark, as an experiment, please try this at various multiples of 1/120
second (83mSec):
1/120, 2/120, 3/120, 4/120, 5/120 -> 1/120, 1/60, 1/40, 1/30, 1/24, 1/20
Since the light is effectively a rectified sine wave, any time you
integrate (expose) over a half power cycle (1/20), you should get
exactly a full cycle of the light, and it should come out even with no
banding.
If you do run an experiment where you just cycle through exposure
times from, for example, 1/500 down to 1/5, at 1/3 stop (1dB) and post
the results, that should be a very cool demonstration of
aliasing/nyquist rate etc. and I've got some science teacher friends
who'd probably really appreciate that gallery being up on the web.
</signal processing geek>
--
Larry Colen [email protected] (postbox on min4est) http://red4est.com/lrc
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