I need to ask for a favor, as my experience with the Speedlights is quite limited.
Iím trying to find out what would be the proper techniques for using Better Beamers and if the flash range can be extended by using aluminum foil (as one of the quick DIY options).
A little bit of background. Iím planning to go on a remote island for birding this Saturday/Sunday (depending on a weather). My main setup will be D7000, Sigma 50-500 OS, GT5540LS, Q20 and Sidekick and I will have with me SB-910 as well. I also have a FX-6 better beamer on order to be delivered tomorrow, right before the event. Iím not sure if Iíll be using flash at all but itís better be ready than sorry. At least the flash can put some sparks in the birdís eyes and that would be a nice addition to the image (at least as I see it).
From the pictures the better beamer is nothing but two black side panels holding flat sheet magnifying glass without top and bottom sides. The following questions are in my mind that I cannot figure out on my own:
1. Why are the sides made not from reflective materials? As far as I suspect the reflective material will preserve more light to go through the magnifying glass. Are any possible drawbacks if Iíll cover the sides with aluminum foil? Any thought on that?
2. Why there are no top and bottom sides? I suspect it is done for better ventilation of the flash head to prevent the flash from overheating. But at least the half if the BB that closer to the lens probably can be made reflective from all four sides, leaving open vents right next to the flash head. (At least as I see it)
3. But my main question would be on how to properly use the better beamer. In matrix metering mode the flash output power mostly controlled by the distance to the object. The better beamer brings modification into Nikonís power output algorithm. Potentially at the shorter distances the object can be overexposed. So what to do in such cases? Remove camera from matrix metering mode? CW or spot? Put SB910 into TTL mode instead of TTL-BL?
Any suggestions and explanations are appreciated. I do not want just the beginnerís luck Ė I want to understand how to control the lighting situation, especially in tough HDR situation.
#2. "RE: Better Beamer technique" In response to Reply # 1
To the aforementioned: 1. Set the camera to FP high speed sync. 2. Set the flash to TTL (not TTL BL). 3. Dial in -1.7 EV. 4. Set the flash head to 50mm. 5. Now forget about the flash: shoot as you normally would.
I would add: calibrate the aim by shooting some test shots at roughly the distance you are expecting your subject to be at. I find the BB doesn't sit perfectly and you may need to tweak it up or down a bit to get the aim just right.
#4. "RE: Better Beamer technique" In response to Reply # 3
I got the BB today - everything is very simple - setting zoom on the head to 50mm - just points all light to the lens- there is nothing to bounce and that's why there is no reason for reflective side or any other nonsense i've been asking.