When using the Nikon SB-900 (and the SB-600 and SB-800 as well btw.) as a remote flash and the camera as the commander, the built-in flash always fires as well even if it is explicitly disabled in the e3 menu. Even though those timing flashes are of lower intensity, they can be seen clearly if you’re photographing an object with a reflecting surface, including eyes, especially when using a macro lens. At times, this is a very unpleasant effect. Is there a way to prevent the built-in camera flash from firing when using a Nikon CLS remote flash?
Unfortunately, it’s not possible to prevent the built-in flash from firing when the camera is in commander mode. There a few workarounds to prevent the built-in flash from appearing in the resulting photo. This is what the Nikon D700 manual says about how to prevent the timing flashes from appearing in a photo:
To prevent timing flashes emitted by the built-in flash from appearing in photographs taken at short range, choose low ISO sensitivities or small apertures (large f-numbers) or use an optional SG-3IR infrared panel for the built-in flash
And this is what the Nikon SG-3IR looks like:
I don’t have a SG-3IR at hand so I tried to cover the internal flash with black duct tape but the remote flash didn’t fire anymore. Obviously, the remote flash needs the pre-flashes from the camera to fire. Looking at the SG-3IR I realized that it doesn’t cover the built-in flash entirely, the plastic panel sits a few inches in front of the flash. Using the lens cover and pressing it to the Nikon logo in front of the camera I was finally able to make the built-in flash disappear in the resulting photo. You could also use your hand to shield the built-in flash but I found it more comfortable to use the lens cover. Whatever method you use, just make sure you don’t cover the internal flash entirely because the remote flash wouldn’t fire anymore, resulting in an underexposed photo.
If you know of another DYI solution, please feel free to leave a comment.