Nikon d90 and SB600 External Flash question

[ebypic]

Hello All,

I recently purchased an SB-600 Flash for my Nikon D90. For a current assignment I am trying to take pictures of smoke in front of a black back drop. To do this I am setting up my external flash on the side which will illuminate the smoke.

I've figured out how to use the camera and flash via wireless, but I can't figure out how to engage the external flash without having the built in flash on my camera go off.

Would greatly appreciate if anyone can point me in the right direction. Thanks

[zona5101]

In commander mode on the D90 you can set the pop up to not fire.
it is in the custom setting under section "e" flash bracketing
select e2
for the built in flash arrow through the selections until it reads "--" for the built in.
The other sections are "ttl" and "m" for manual iirc...

[ebypic]

Thanks very much.I have it set up exactly the way you described it, but the built in flash is still going off. Is there another setting I'm missing? Thanks,

[zona5101]

Originally Posted by ebypic

Thanks very much.I have it set up exactly the way you described it, but the built in flash is still going off. Is there another setting I'm missing? Thanks,

it is going off before the exposure to trip the sb600. You are not seeing it in the resulting image are you???

[ebypic]

Ah, never thought of that. I just tested it and i am seeing the built in flash affect the picture.

[zona5101]

Originally Posted by ebypic

Ah, never thought of that. I just tested it and i am seeing the built in flash affect the picture.

Ok i mistyped in my last post...it preflashes to read the light not to trip the sb unit. The sb trigger is not an optical. It does preflash. ....let me test...

ok I am sorry i do not know...I grabbed mine and took a picture in a mirror with the sb off camera triggered in commander mode. In the resulting image both flashes are visible

[ebypic]

Originally Posted by zona5101

Ok i mistyped in my last post...it preflashes to read the light not to trip the sb unit. The sb trigger is not an optical. It does preflash. ....let me test...

ok I am sorry i do not know...I grabbed mine and took a picture in a mirror with the sb off camera triggered in commander mode. In the resulting image both flashes are visible

Hmmm...no worries. Thanks again for your help / input, I really appreciate it.

I'm guessing I'm stuck with my camera's built in flash going off in order to trigger the sb flash?

[scootermcq]

Originally Posted by ebypic

Hmmm...no worries. Thanks again for your help / input, I really appreciate it.

I'm guessing I'm stuck with my camera's built in flash going off in order to trigger the sb flash?

Yup, but if you cover the on board flash with some developed negative leader it will prevent it from showing in image, but let the infrared through to trip the SB600

[OsmosisStudios]

If you have the on-board flash set to "--", it doesnt affect exposure. If you're seeing it, then either your flash is faulty or your imagining things. If you really need to, Nikon make something they call the SG3-IR that sits in the hotshoe and blocks the light from the flash but doesnt block the triggering flash.

[scootermcq]

Originally Posted by OsmosisStudios

If you have the on-board flash set to "--", it doesnt affect exposure. If you're seeing it, then either your flash is faulty or your imagining things. .

Not necessarily... Nikon does say that with close range, rear curtain, or large aperture shots the on board flash can affect the results and that is why they make the SG-3IR. (or you can use exposed negatives for less money)

I would have to assume you are fairly close to photograph smoke, in which case, the on board flash may affect the image.