Flashy

[nikonian]

HI.
I know it is an impossible query that I have, but does anybody know what setup on the D90 fires either 2 or 3 flashes using the on board pop up flash.

[greenwing]

It would help if we knew what you were trying to achieve, or were struggling to understand. There are settings that would let you fire many other speedlights using the onboard flash, there are settings that will let you fire the onboard flash several times during an exposure. The onboard flash will normally fire (apparently) 2 or 3 times in an exposure.

Be more expressive with your question, and you'll get better quality answers.

Chris

[nikonian]

That is what I am trying to sort out. Normal flash from the pop up does fire 2 or 3 flashes. Now in plain English what set up decides the number of flashes from the pop up flash.

[greenwing]

Exactly how many flash pulses there are, I'm not sure.

There are, as far as I can tell,two groups of flashes.

There's the pre-flash, before the shutter opens. iTTL flash depends on the return from the first sequence of pre-flashes (before the shutter opens) to determine the flash power to use during the exposure. If you set the AF-L/AE-L button to FV Lock, pressing that button will get the pre-flash over & done with, the camera will decide how much flash power to use in subsequent shots (until you do it again, or change shooting mode, or stuff like that), and you won't get the pre-flash, just the flash on the exposure.

In commander mode, the pop-up flash might give a total of 12 pulses in the pre-flash sequence, with 2 flashes from each of the remote groups. The pulses from the pop-up are probably too close together to see.

If you go to manual flash mode rather than TTL, the pre-flash isn't needed at all.

After the shutter opens, probably when the flash is required (so it may be long after the shutter opens if we're talking rear sync) the flash delivers a quick pulse and then fires at the required power. I'm not sure if that quick pulse happens if the flash is not in commander mode.

Hope this helps
Chris

[PaulMontgomery]

According to dpreview, repeating flash is set in menu item e2. You set the rate and the number of flashes you want.

[greenwing]

Don't you love it when someone thanks you for your help?

[PaulMontgomery]

:-)
I'll give him the benefit of the doubt - maybe he has got a life and doesn't spend all day on the computer like me...

[poopeson]

go to your "menu", go to "custom setting menu" , select "built-in flash", choose "commander" mode.

in commander mode, the flash fires 2-3 times.