Flash stop motion, need help.....

[USM IS]

I went and looked in the mirror, cuz that is where the problem originates. But didn't find the answer! I can stop the splash, but not the drop motion. Drop distance of fruit is only 4"..... Any idea's?. Using two Photogenic 2500DR's, on each side, with a 580EX up close in center. Shutter speed is 1/320, as fast as it will sync. F /22 for depth of field, 24-70mm L, 1D Mark III on tripod with ballhead and remote release. It's not the equipment, so educate me, PLEASE......Mike

 

[Overread]

At a guess it looks like the flash is not dominant enough as the main lighting source - surprising as you are stopping all the way down to f22 (personaly I would open up to f16 at the least since f22 your shots will appear softer because of diffraction no matter how good the shot is).

Try shooting in darker conditions where the flash light is the most dominant - so that without flash the shot would be black (ie underexposed). That way only the moment when flash is used will register on the sensor.

 

[USM IS]

But I was in the basement with just the modeling lights on the 2500's for light. And it was F/22 because the flash was BRIGHT! It was very dominate! And I had the 2500's pointed directly at plate, not bounced from umbrella's....Mike

 

[Overread]

Wait how are you setting the power on your flashes? You should just be able to turn their power down rather than have to shoot at f22. Also if the flash light is dominant then it has to be due to the duration of the flashes light itself. Are (because I have no idea) these regular flahes like a speedlite that just send out a pulse of light or are they sending out a longer duration of light?

 

[rallysman]

You should be able to turn the power down, which will give a shorter output time.

Here's my thread playing with high speed stuff:

http://www.thephotoforum.com/forum/general-gallery/187725-high-speed-photos-how.html

 

[NateWagner]

also, speedlights typically have faster pulse length than do things like monoblocs. Try it with just the 580 and see what happens.

 

[LearnMyShot]

I think it's flash duration....shoot the flash on as low a power as possible and open up as much as you can...that should help....or hold the strawberry up with a stick from behind going straight back and through the background or connected to the bowl...then it's not moving and you're done!!!

 

[Derrel]

You should be able to turn the power down, which will give a shorter output time.

Actually, the Photogenic monolights have longer (slower) flash durations as their power levels are reduced...this is also the case with Alien Bee monolights, and a few others. http://www.photogenic.com/download.aspx?type=manual&id=25

The shutter speed you are using is 1/320 second, and the stated max speed on a 1D Mark III is 1/250 second, so I am assuming that the speedlight flash is defaulting to an FP or high-speed synch setting--which is actually a long, slooooooow series of micro-flash bursts, and not a single,discrete flash burst. High Speed Sync will lead to blurred motion on all sorts of stop-action motion scenarios--birds in daylight, water drop scenes, all types of rapid motion will be blurred if a Canon or Nikon flash is operating in High Speed Sync or Focal Plane Sync mode. So, the flash synch shutter speed of 1/320 doesn't make a lot of sense to me.

I am not sure why this scene needs three lights. Regardless, with the Photogenic monolights, the shortest duration flash will be at Full power,not at a fractional power level. Not sure how the 580 is being set either--if it is in a manual mode at higher power, its flash duration could be INCREDIBLY SLOW!!!! In actual measurements, a 580 EX-11 at Full power could drag your shutter speed down as slow at 1/169 second with the sensor .5 feet from the scene, and at 2.0 feet, a 580 EX-II at Full power can be as slow as 1/177 second.

Again, the actual flash durations can be pretty slow The Rod And Cone: Flash Durations for Canon 580EX II and Vivitar 285HV and so, unfortunately, I think the idea that the problem is not the equipment is in error--I would say it *is the equipment* that is causing the blurring on the dropping strawberry. Or, in another way of looking at it, the *manner* in which the equipment is being utilized is causing a problem.

If you look at the rodandcone page on speedlight duration, there are some tips and comments there on how speedlight durations actually change,depending on how far the sensor is from the subject--at close-up ranges with a lot of white in the background, the durations are much,much slower and longer than when the sensor is farther away,and of course, the Photogenic monolights get slower at lower power levels, while the speedlights get shorter at lower power levels.

So, looking at everything, it seems like there re a couple of likely culprits. What does the scene look like exposed with NO flash?? Doesn't f/22 at 1/320 yield a pretty dark scene? The blur on the berry looks very well-exposed and bright; individual seeds are visible, and it's not "Dark", so it looks to me like basically, too long of a flash duration, and I am wondering about the 580 and the 1/320 speed shifting the camera to the High Speed Sync mode,and causing the rapid-fire 80 hertz (??) HSS burst which allows the dropping berry to blur.

 

[Aye-non Oh-non Imus]

I don't shoot Canon equipment, but i think you exceeded the max sync speed. It will likely be 1/200s or 1/250s. Chances are this is causing your motion blur, rather than freezing the action. Additionally, f/22 is not really needed.... I would think f/16 max and more likely around f/8, even up to f/4-f/5.6.

Notice the hard shadows in the front of the bowl and behind the fruit. Your lighting placement, intensity or modifers are off. I would look at sorting that out first, then the other issues. If you're at f/22, why is there so little detail in the image?

 

[NateWagner]

So, to sum up... it's not necessarily your equipment that is bad, it is how it was used.

The 580 should be able to do this by itself, but you will want to be at or below xsync speed (as Derrel said that would be 1/250).

I wouldn't necessarily want to use the big lights, but I'm sure it could (probably) be done with them. In the way you are using your lights you are losing their flash stopping power.

 

[iflynething]

f/8, 1/128 power and adjust lights to get the right lighting

Make sure to get your flash as close as possible and the lowest possible setting as possible, put it on manual!

~Michael~

 

[USM IS]

I had the 2500's turned down to 50% and was using a 4 stop ND filter because it was TOO BRIGHT. The 2500's were on the left and right at 9' away, angled down, the 580 was on manual at 1/4 power to the front left at 1' from bowl. I couldn't back out the 2500's any more because of limited space. I had worked up from 1/125 sec shutter speed to the 1/320 with no change in blur, was thinking maybe the duration on the Photogenic's was maybe a contributing problem. Thanks for all the input, will try and redo this scene. Was originally trying this with Oreo's, but the dang things would spin, I wanted to catch the OREO written on cookie (DREAM ON).......DANG NICE WATER DROP PICS by they way iflynething......MIke

 

[NateWagner]

one other question...

Why on earth were you using ISO 800? You should be able to cut out at least 3 stops of light by going down to ISO 100. With which you could get f13ish, rather than the f/22. Meanwhile as was already mentioned knock down the shutter speed to the sync speed or a little below (that shouldn't affect your exposure as there is little ambient to worry about).

 

[Flash Harry]

Flash freezes subject, try it, shutter speed is immaterial as long as no ambient light, so studio controlled, put the camera to bulb mode in the dark, drop strawberry/fire flash, close shutter. This is basic photography knowledge, I've done it with an egg dropping onto someones head, only difference was I used an infra red beam broken by the egg to trigger the flash at a specific point, metered flash from that point for whichever aperture you require for DOF.

Dragging the shutter to let in ambient happens when outdoor in daylight, studio controlled lighting is a different kettle altogether. H

 

[NateWagner]

Yes Flash Harry, flash does freeze a subject... it does so because the flash of light occurs at a tiny precise instant thus almost all of the exposure is completed within that tiny instant.

However, as we have been discussing, there are variations. For example, if he was shooting in HSS/FP then there would have been a bunch of those little instants thus getting rid of the freezing ability of flash (because the flash would be firing throughout the entire exposure).

Also, typically with monoblocs (as we have discussed) the flash duration is much slower than that of a speedlight, and they are even slower still if you shoot with less power. (I believe this is due to the arc they have to make in order to keep the same color of flash... but I could be mistaken).