SB800 Question

[Sandy Feet]

Hi Guys,

Having a play with the SB800 in wireless remote mode and using the onboard flash to trigger (D70).

my question is how do I adjust the power output on the SB800 in remote mode, do I set it before going into remote or is there some way to adjust on the fly.

Playing with lighting I think it will be a pain to keep going into and out of remote mode to make adjustments

Thanks
Rod

[Oz_Beachside]

I think you might be trying to use two different technologies.

SB800 remote mode, as far as I know takes the settings from the master. The master can be the built in flash of a D200 set to commander mode, an onbaord SB800, or an onboard SU-800 (the flash body with only the red panel, but no flash).

If you have a D70, the built in flash can be dialled down to minimum power, and trigger the SB800 when in SU-4 mode. SU-4 mode is a wireless trigger mode, but all the power settings remain set directly on the SB800.

I tried what you are trying on a friends D70 becasue I am used to the D200, and its doesnt have the function.

hope I am on track, and that helps

[digitor]

If you set the D70 flash to Commander mode TTL, and set the SB800 to Channel 3 group A, then it will work remotely, and you can dial the exposure up and down using the flash comp setting on the camera.

You can also select AA or manual modes on the D70 if you don't want to use TTL. In manual you can set the power of the remote SB800 from 1/1 down to 1/128 using the D70 menu.

Cheers

[Sandy Feet]

Basically what I am trying to do is just use the SB800 off camera and dial the onboard down to act as just a trigger.

Maybe I need to fashion something to block the effect of the onboard but direct it as a trigger

[Oz_Beachside]

If you set the D70 flash to Commander mode TTL, and set the SB800 to Channel 3 group A, then it will work remotely, and you can dial the exposure up and down using the flash comp setting on the camera.

You can also select AA or manual modes on the D70 if you don't want to use TTL. In manual you can set the power of the remote SB800 from 1/1 down to 1/128 using the D70 menu.

Cheers

thanks for correcting me, sorry for the bump steer.

[Oz_Beachside]

Basically what I am trying to do is just use the SB800 off camera and dial the onboard down to act as just a trigger.

Maybe I need to fashion something to block the effect of the onboard but direct it as a trigger

if you use commander mode, the visible light fires before the shutter, so it should not actually contribute to the exposure (even though you can see it).

[Sandy Feet]

Thanks Guys will play some more

[Mr Darcy]

If you use the Commander mode as suggested by digitor, the PopUp(PU) on the D70 contributes only minimally. It will only be a problem if you are photographing highly reflective objects
What I think is happening is the Preflashes say "Fire flash #3 at xx power on my Mark..." Then there is a minimal power burst from the PU to say "Go"

This minimal output from the PU on shuttter open can generally be ignored, but if, for example, you are shooting a mirror or a bottle, the direct glare can be obvious.

To eliminate it completely, cover the PU with an infrared filter (the developed leader from a slide film works well!) The SB800's sensor works on the infrared part of the burst, so the signal to the slave is not blocked. You can also use a card between the PU and subject, but this will reduce the range of the signal to the remote.


HTH

[Pehpsi]

Bit off topic, but i'm curious as to what kind of shutter speeds you can get with the SB800 when shooting indoors in low light?

[ATJ]

Bit off topic, but i'm curious as to what kind of shutter speeds you can get with the SB800 when shooting indoors in low light?

I believe that depends more on the camera body than the flash. It will depend on the flash sync speed which limits the highest shutter speed. It will also depend on whether you use front or rear curtain. As for the lowest shutter speed, there are no restrictions.

[Pehpsi]

Thanks for the speedy reply..

Does the flash change it's strength depending on what shutter/aperture combo you choose?

[gstark]

Thanks for the speedy reply..

Does the flash change it's strength depending on what shutter/aperture combo you choose?

As a generalisation,

Shutter speed: no.

Aperture: yes.

[ATJ]

The way modern flashes change their "strength" is by varying the duration of the flash. In full mode they are something like 1/1000", as you cut the power down, the duration will be less. e.g. half power is probably 1/2000", quarter, 1/4000".

The duration, even at full power is such that as long as the shutter speed is less than or equal to the shutter speed for the camera (e.g. 1/500" for the D70), it makes no difference to the exposure from the flash.

The aperture does make a difference. The smaller the aperture, the longer the duration of the flash needs to be to give an appropriate exposure.

If you have the camera/flash set to iTTL, the flash sends out one or more very short duration flashes before the main one. The camera determines how much light is reflected and uses that to determine the duration of the main flash. The aperture you set will influence how much light enters the lens and so influences the "strength" of the flash.

So to answer your question (based on the above), the strength of the flash will change depending on the aperture chosen, if you are using iTTL.

[ATJ]

Gary is far more succinct than me.

[Pehpsi]

Awesome, thanks for the info guys.

I haven't had much experience with flash before, but with the band stuff i'm getting into i'm going to need it for certain venues and also the group type shots.

[gstark]

The best thing to do (I've found) is to use a slow-ish shutter speed - 1/20, 1/30, 1/60 - and use FEC to pull your flash back by about 0.7 - 1.3 stops.

If you're able to come to the Bald Faced Stag at Leichhardt tomorrow night, I'll be happy to give you a few pointers with this sort of technique.

And after all, the more you practice and experiment, the better you'll become at this.

[Pehpsi]

Don't have my car for a few days, so Leichhardt is a bit far for me, but cheers anyway

Just waiting for some money to come in, then it's off to the shops for a spankin' new flash.. I'll let ya know when I get it

James.