Dennis Havel
New member
Five drops..five shots
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Shot Drop Shot
- Thread starter Dennis Havel
- Start date
Charles L Webster
pro member
Nice! Would you care to share your strobe and droplet timing apparatus with us?
jake klein
Member
Definitely nice! I would try moving your strobes closer so you can bring down the power on them, thus increasing the flash duration speed.
Then if you used rear curtain flash you could get some motion blur on the pellet from ambient while still freezing motion on the tip of the pellet.
Then if you used rear curtain flash you could get some motion blur on the pellet from ambient while still freezing motion on the tip of the pellet.
Dennis Havel
New member
The strobe is maxed at 1/128th power (1/38,500sec) on these shots.
Not possible to use rear curtain. The event happens much too quickly to use the shutter for exposure. There is no ambient light present.
The exposure is made with shutter opened prior to drop release and closed after impact. The strobe is controlled independently from the camera.
I can cause motion blur for the pellet very easily; the problem is that the resulting splash water is also blurred causing a blurry mess.
Here's a single drop shot while falling:
jake klein
Member
Ok I understand now. So how do yo cause the motion blur? Is there anyway to isolate that to just the pellet?
Dennis Havel
New member
Up to a point. Increasing the speed of the pellet beyond the speed capability of the strobe will result in more pellet blur. However, the resulting impact splash will be faster as well.
These shots, of which I have hundreds, are the result of very precise timing calculations of drop speed, pellet speed, and time delay of gun firing.
For the single falling drop image posted above, the drop presents itself as a target for 31/100,000second. The pellet speed is approx 850fps.
Crop of above
Bart_van_der_Wolf
pro member
Here's a single drop shot while falling:
Hi Dennis,
Nice shot. Was that with an acoustic trigger or with a light trap?
Cheers,
Bart
Dennis Havel
New member
The timing components are comprised of two intervolometers, 2 infrared photo gates, a valve solenoid, a gun trigger solenoid, and a 24vDC relay. All have to be in perfect sync along with the strobe and camera for the shot to work.
Single falling drop
Dennis Havel
New member
This event happens much too quickly to use an acoustic trigger. I don't know what a "light trap" is.
The entire sequence is precisely timed with 2 intervolometers. The timing sequence is started upon releasing a single drop which falls through 2 infrared detectors which may be what you call a "light trap".
Calculations were done to determine drop velocity and time to reach the impact point. Measurements were done to determine how long it takes the gun trigger solenoid to activate the gun trigger and for the pellet to travel to the impact point.
The drop time calculation was used to determine strobe firing delay which occurs when the drop is precisely at the impact point and aligned with the path of the pellet. The strobe firing can be adjusted to capture an image before, during, or after impact.
