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| Nikon D4, 28-300mm, ISO 12,800, ƒ/5.6, 1/400 — Flashes used (4) Alienbees B1600 with 11″ long throw reflectors with PocketWizard Plus II receivers and being triggered by the PocketWizard Mini TT1. |
High Speed Flash vs No Flash
In the photo above I used a flash with an output just about the same output as the existing light.
This is the histogram for the above photo.
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| Nikon D4, 120-300mm, ISO 11,400, ƒ/2.8, 1/1000 |
Here is another photo where strobes were not used. I had to change to a faster lens and used a faster shutter speed.
This is the histogram for the second photo. There are two things I notice that are different. First of all the shadows in the available light photo have less information as compared to the photo using flash. Second the entire dynamic range appears greater with the flash, which results in less noise in the photo.
ISO 25,600
I wanted to just see what the Nikon D4 looked like at 25,600 without strobes. Here is that result. I am showing the same player so there is little variation as possible except for ISO.
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| Nikon D4, 120-300mm, ISO 25,600, ƒ/4, 1/1250 |
Here is the histogram for ISO 25,600
Color Temperature
The ability of a camera to reproduce color accurately depends a great deal upon the color space with which the object is photographed. The dynamic range of color is the greatest with Daylight or 5500º Kelvin. As you move away from this color temperature to the sodium vapor lights in this gym that are 3700º Kelvin and then must add 27+ magenta to color correct this to get a neutral grey the color space actually shrinks. The dynamic range is less.
For the most accurate color if we had used only the strobes and no ambient light at all the color would have been the most accurate. Also, I could not have bounced the flashes off the ceiling, but would have to point them straight at the volleyball players. You see the flash that is bounced will have a color shift of whatever it bounces off. If the ceiling was red then there would be a red tent to the light.
Setup
Here is a photo of one of the four Alienbees B1600 with the 11″ long throw reflectors. You can also see the PocketWizard Plus II used to trigger the flash. I dialed down the flash output to 1/8 power. Again with todays full framed high ISO camera chips the results are quite acceptable and the flash is less disturbing to those in the room.
This is a wider shot of the room where you can see the results of all four strobes going off.
This is the histogram for the overall shot above.
Here is that same angle with no flashes.
This is the histogram for the available light photo.
One last comparison
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| Nikon D4, 28-300mm, ISO 12,800, ƒ/5.6, 1/400 — Flashes used |
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| Nikon D4, 28-300mm, ISO 12,800, ƒ/5.6, 1/400 — No Flash |
High Speed Flash Sync
You may have noticed that the flash shots were done with studio strobes and syncing faster than the 1/250 sync speed for the Nikon D4. How did I do that?
Here is an explanation from the PocketWizard website.
PocketWizard’s HyperSync™ feature throws x-sync out the window, allowing never before possible shutter speeds with full power flash – any full power flash. With some camera and flash combinations even 1/8000th second is possible. (Alienbees with the Nikon would only sync up to 1/400)
HyperSync is simply the ControlTL® system’s unique ability to adjust the timing of the flash burst so that you can use as much of the light output as possible as the shutter opening passes over your sensor. With the systems “through-the-shoe” communication, a ControlTL transmitter with HyperSync can automatically detect the camera type connected to it as well as the shutter speed. Read more …