I found an internet post recently where another photographer had claimed to have synced his flash at 1/8000 of a second, the problem was, the images that he had uploaded were not compelling. I set out to test his technique, which I was very skeptical of to say the least. His idea was simple, using a rigged flash delay he would “grab” only a portion of the amount of flash output by setting the camera to a very high shutter speed. I recreated his experiment a bit differently by attaching an optical slave to a SB-800 flash set to manual with duct tape to prevent any light from reaching my subject. The optical slave was wired to a pocketwizard radio sync, with the slave sync attached to a Broncolor Mobil pack. Apparently this pack is ideal for this technique because it has a slow flash burst of 1/680 of a second letting you grab a portion of the flash curve at 1/8000 second while still maintaining a decent color balance. The slight delay in the speedlight, and the slight delay with the radio slave was enough to make this meatball rig work properly. In the figure below, I am trying to illustrate what I believe is happening during the flash cycle.
The above video shows a shutter cycle at 1/4000th of a second. As you can see, the shutter never fully opens, just a slit of the front and rear curtains scans the sensor during exposure. Now if you can imagine a flash burst that was faster than this shutter cycle, you can see why you would only see a thin slit in your image. What we are doing with the Broncolor is using a flash duration that is longer than the shutter cycle so that the flash is on during the whole 1/8000 of a second sweep of the shutter.
Color balance is of key concern when taking only a portion of a flash curve. The first part of the curve is quite blue in color temperature, with the temperature gradually getting warmer as the flash burst fades. I used a gray card and took a custom white balance with the settings as follows.
Nikon D3 ISO 1000 F22 @ 1/8000 second.
Sb-800 speedlight on manual 1/16 connected to camera with a duct-taped peanut slave on the front. Pocketwizard sender connected to peanut slave.
Broncolor Mobil at full power 1200 joules, pocketwizard receiver.
Pulso head with gridded beauty dish and bounce reflector.
The above water drops from the top of the page are shot at exactly these settings.
The holy grail of beverage photography is the ability to sync a flash at a high enough speed to stop the liquid, and beverage photographers have been using exotic and expensive lighting to achieve these results. Beverage photographers have traditionally used very high power strobes, dialed to the minimum power settings to create the shortest flash durations. With the advent of the fast flash duration, Profoto and the Broncolor studio packs boast the ability to achive durations as fast as 1/8000 (Broncolor Scoro) of a second, but let’s face it, a Scoro pack is ten grand! Using affordable power packs like a Mobil (any older design budget flash unit with a slow duration should work) the ability to freeze liquid in mid air can be applied by the average photographer with more modest equipment.
The real difficulty in shooting a “pour” is not the flash sync. I found that once the technical part of my flash duration was under control the real problem was getting the liquid to behave in a way that is visually pleasing. Liquids tend to froth and foam, and to counteract that I added a bit of salt to the water above.
For this test of a wine pour, I used a frosted shooting table and a bowl pressed against the back side of the plex to create a pleasing gradient. The procedure of testing this pour trashed my kitchen- wine EVERYWHERE, paper towels on the floor, wine spatter on my lens and camera, clothing- a disaster. The result is still beyond sloppy, and nowhere near what I want, but this is testing right? The key, as in all food photography, is styling. Everything must be perfectly clean and spotless. This is time consuming when you shoot a pour, the glass and shooting table must be cleaned, the set must be be refreshed, camera refocused, and another pour is attempted. This process repeats many, many times and you wind up with a kitchen soaked with lightly salted red wine. I believe the key is to mount a hose in a place to give a consistent angle of pour and create a system that can be tweeked a little at a time to create the desired result more accurately.
I am in no way finished with my high speed sync testing with beverage pours, there is a long way to go. The beauty of the technique is the ability to see the world in frozen time. Liquids look like they are carved from glass at 1/8000 of a second, it is surreal. I will update this post with finished images of the next test as soon as possible. Let me know if you have any questions, and I will do my best to answer them.