Hi.
* Could I really have a high speed shot in daylight at or above 1/30000"? If so is the DoF workable or does the aperture required to allow enough light effect this
* If so, is it theoretically possible to use my controller which obviously outputs a signal (I guess I need to measure it) in conjunction with a USB trigger, and using some sort relay, to fire the camera's shutter? If so would the delay in this be minimal (the USB side)
* Is motion detection a potential trigger option too? I.e. response times quite quick and or a delay programmable?
* Are there any other triggering options bearing in mind it may need to be sound based or beam tripping. Needs to react quickly and have variability of delay
* CHDK and high shutter speed overrides is debatable. I don't know if any camera actually pulls 1/30000th.
* USB firing delay when using the falling edge (=sync) is fairly consistent and < 60ms for most cameras.
* While you can add delay to the motion detection reaction, it is probably not the best choice here.
* Your best bet for triggering when sub-second accuracy is required is to use an external trigger.
There is a Casio camera that has a theoretical 1/40,000 shutter speed out of the box but feedback I've seen has suggested it really isn't that workable due to the lighting requirements.
Do not be seduced by the absurd claims of very high shutter speeds.
This has been discussed here (somewhere) and the fastest speed is nothing like 1/40,000 sec.
If it was, how would you get enough light.
But it's
so seductive! :b Doing the "dremel speed test" some people have measured very high overrides, so you
can get high shutter speeds on certain cameras; I know I can shoot 1/15000th on the SX100, and probably shorter. But as you both point out, how in the world are you going to light the scene? Here's a picture of the noon day sun with clouds:
SX100, ISO80, f/8.0, 1/16000th, so even @ f/2.8... multiple PAR64s? 500w halogens? 1000w metal halides? Your set will be melting.
I've found the comparison which includes motion detection times and see 150ms as a figure suggested for the A series cameras I'm looking at.
Here's the problem - the MD shot latency isn't static. LCD display buffer selection is round-robin... this method tightens up the shot-to-shot variance over the previous method, but it's still variable. For my CHDK-capable cameras it varies 5ms-40ms. I'm not sure, but it doesn't seem this would be sufficient for the accuracy required. I would use that external trigger to fire via voltage drop on the USB +V pin.
I am definitely going to have a crack at KAP too. ...
Crack. Interesting choice of words. :b Just consider the camera disposable, and the choice is clear. Cheapest! I'm sure experienced KAP veterans have sent $1000 rigs into the dirt/water at
"ludicrous speed"... but if you're just starting kite flying in general and flying a DIY picavet off a small delta, your chance of a catastrophic crash & burn is an exercise in statistical probability. Most of these PowerShots are not durable; impact on an extended lens at even the slowest speed (or just dropping from your hand to the floor) can misalign the gear teeth on the lens motor, or worse...
I'm fascinated by KAP; not so much the images produced as the dedication and obsessive nature of the KAPpers themselves; it draws you into their world with wide eyes and a big grin. CHDK/SDM & KAP are made for each other.
Not for nothing, but you sound like someone who's going to have much more fun with a CHDK/SDM-capable Canon than a Casio. Just sayin'.
