SB-900 Remote wireless flash - pop-up flash still fires...

You can make your own substitute for the Nikon SG-31R IR panel from floppy disk material. Tape or just hold in front of the pop up and it blocks almost all of the visible light.

I have now tried this and can report that is works. My SB600 on the other side of the room will still fire when the pop up is set to "---" (min. output) when I hold the floppy material against the front of it. Shooting directly into a mirror and the pop up appears as a yellow rectangle through the floppy material. Without the filter I shows up as a bright source even when set to "---"

Follow this to the source link.
http://forums.dpreview.com/forums/read.asp?forum=1039&message=37990003

Graystar wrote:

I see that you already got your answer (it’s the wireless “go” signal)...just wanted to add a few more things.

The higher the ISO the greater the effect of the command signal. So shoot at a low ISO to minimize the contribution of light.

Another way to reduce the commander signal is to buy the Nikon SG-31R IR Panel. It blocks the visible light from flash but allows the IR light through. It's still not perfect, but it makes a difference. For 12 bucks it’s something to try.

See it here...
http://www.amazon.com/Nikon-SG-31R-Panel-Built-Flash/dp/B000E1G0LI

The commander signal always adds light to the scene because it fires immediately after the shutter fully opens. If you want to eliminate the effect of the commander signal entirely, use Auto FP mode. Enable Auto FP with Custom Setting e5:Auto FP. Set your shutter to 1/250 for the most light. With Auto FP, the “go” signal comes immediately before the shutter begins to open. So if conditions allow the use of Auto FP (there’s a power loss that has to be accounted for) then that’s the best way to avoid the commander signal adding light to your image.

One last option for indoor use that I don't think anyone has ever tried is the Lightscoop. Lightscoop is a device designed to bounce your built-in flash off the ceiling. Personally, that sound dubious to me, but there's no reason why it wouldn't work just fine to bounce the commander signal off the ceiling. It is well known that when shooting indoors you rarely need line-of-sight for the Nikon Wireless flash to work. So bouncing off the ceiling should be fine. You will still make a contribution of light to the scene, but after being bounced off the ceiling, I doubt it will be visible. More important is the fact that you won't get a reflection in reflective objects such as glass.

See Lightscoop here...
http://www.lightscoop.com/

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