Hi I thought I would just experiment with using my SB-700 off camera and it appears I may have a fault. I mounted a flash meter on a stand to measure light. The SB-700 has been set to Remote, Group A, Channel 1 with the sensor pointing at the camera. The camera has been set to Commander Mode, Built In Flash - -, Group A Manual, Comp 1/1. Camera in Manual Mode, 125th @ f4 with pop-up flash deployed. Flash to meter distance 1.5 metres. The pre-flash from the camera fires and I get a reading of 125th @ f0.8 ? I try varying the Comp output on the commander but the output will not change. I shift the flash to manual mode and fire the test button and I get 125th @ f14.2. Manually changing the flash output works perfectly. Am I doing something wrong?
I'll take a stab at this. So just to clarify things, is the SB-700 firing or not? I set my D7000 and SB-700 to the same settings and it fires just fine. I don't have a handheld light meter as yet, so I cannot duplicate that part of the test.
EDIT: Even with the onboard flash set to "--" it will still fire at reduced output, hence why you should use the slip on IR panel that sits on your hot shoe which Nikon sells. I forget the part number. Me I am going with an SU-800, which arrives this week. So, since you set the onboard flash to not fire, there is no comp setting for it.
Unless you flash meter can adjust for the pre-flashes used to compute the power setting of the remote unit and set the computed power level of the remote unit, you will not get an accurate measurement. Triggering the camera will run the full pre-flash sequence and the trigger flash on the camera and the exposure flash of the remote.
You could try using the FV lock to lock in the results of the pre-flashes in the remote and then try triggering the camera for the flash meter. This would result in only the trigger flash from the camera and the exposure flash of the remote. Just like manually setting the remote unit in the SU-4 mode, trigger flash and exposure flash.
AWS, Advance Wireless System, in Nikon CLS Speedlights use visible light at low power levels to communicate to the remote units. To see a full discussion of this look at the post "New CLS Preflash Sequence Images".
You can eliminate the visible pre-flashes by using the SG-3IR Pop-up flash filter. This might change your results.
>You can eliminate the visible pre-flashes by using the SG-3IR >Pop-up flash filter. This might change your results. > Hi George You were spot on with your analysis. It was metering the pre-flash. I got 2 layers of tissue paper and fixed it over the pop-up flash. Then ran through from 1/1 to 1/128 power and the meter is now giving me correct readings. I shall now have to invest in the SG-31R to replace my tissue paper Many thanks for your help, I was losing faith in my my flashgun.