Question about Nikon CLS

[Turo]

I am not very familiar with CLS so after doing some google searching, I turn to you guys.

Assume you have a D300 or D700 with one SB600 being fired remotely using the SLR body as the commander. Now suppose you want to add a second flash to be also fired remotely. Is there any advantage of getting the SB800 as the second flash as opposed to another SB600 if the camera will be used as commander? Assume that more than 2 flashes will never be used, and none of the additional features of the 800 are necessary for the setup (longer range over the 600, etc...).

I know the D300/D700 have 2 channels for CLS, so they should be able to fire both the SB600's with no problems, correct? I know the popup flash is used to trigger the speedlights, but does the popup flash contribute to the light/exposure of the scene?

[jcon]

If you are positive you will never need more than the 2 speed lights and wont need the added power of the SB800, then another 600 would suit you perfectly. Everything will fire just fine.

Depending how close you are, the onboard flash could influence the lighting just a tad. More than likely it wont have any effect at all.

[achuang]

If you will never use more than 2 flashes off camera then 2 SB600 would work fine. However, if you're in the situation where you'd like 1 of the speedlights on camera and 1 off camera then you'd need the SB800 as it can be used as a commander.

Yes the D300/D700 will fire 2 SB600 no problem. In the D300/D700/D80/D90 you have the option of allowing the popup to contribute to the exposure or not. However, in my D70s I don't have that option so it doesn't contribute to the exposure. It does contribute when I'm shooting at close range or with a large aperture.

[Dread Pirate Roberts]

With 2 SB600's (or 400's or 800's) triggered by pop up.
There's a menu for flash where you select either TTL or Commander.
With commander it brings up a table where you can set the pop up to just trigger using infra-red or to use visible light on manual or TTL.
In the table you can set TTL exposure compensation on all the flashes independently, 0, -.3, -0.7 etc.

So you get great flexibility and it's a piece of cake to use.
Took meeting Ssil2000 face to face to work out how to set the SB's to be trigered remotely though. Setting the SB600's isn't intuitive at all, but once you've done it you never need to take them off.

[Rooz]

2 groups, not necessarily 2 flashes.

[Turo]

Ok, so since neither one is a commander, I can assign one speedlight to each group and trigger them via popup flash.

So when it is on infrared, I assume it contributes no light at all to the image? Would this be the way to go then if you only want the off-camera speedlights to contribute light?

Just making sure I am understanding this right, thanks for all the help so far!!!

[jcon]

Setting the On board flash to commander through the menu in camera, then only the remote flashes will contribute to the exposure.

[Turo]

Gotcha, thanks all for the help! :)