How to use flash in a bright scene?

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GaryK26

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If I am shooting an outdoor portrait, say with the subject sat on a rock on the beach and the scene is backlit (eg shooting into the sun), how do I use my flash (430EX) on the subject?

Lets assume that I the scene as a whole exposes at 1/1000 second, F8, ISO100. What I am unsure of is the fact that the flash syncs at 1/250th, so would there not be a mismatch between the flash and the shutter speed?

I could up the aperature accordingly to F16 (or whatever is required to bring the shutter down to 1/250th), but suppose I want to also achieve a narrowish DOF.

Also, for such instances, should I be shooting in Aperature Priority or Manual?

I've probably got this all completely wrong, so I'd appreciate any advice.

Cheers
Gary
 
In this instance the easiest option is to go for high speed sync or focal plane mode (can't remember which is canon and which is nikon). It'll make the flash pulse frequently instead of giving a slower single burst and will allow you to keep the faster shutter speed. It does reduce the range of the flash though.

Or you could use a neutral density filter to bring the exposure back to something like F8 1/250 but you're flash will also need to fight the filter so you'll have to be reasonably close to your subject.
 
GaryK26 said:
What I am unsure of is the fact that the flash syncs at 1/250th, so would there not be a mismatch between the flash and the shutter speed?

I could up the aperature accordingly to F16 (or whatever is required to bring the shutter down to 1/250th), but suppose I want to also achieve a narrowish DOF.
Click to expand...

It depends what kit you have. The Nikon SB600, SB800 & SB900 will all sync with certainly the top end Nikon cameras at speeds up to 1/8000th sec. I am guessing some of the Canon camera/flash combinations do too.

In theory you should be able to open up to f2.8 and shoot at 1/8000th but in reality I'm not sure if the flash effectiveness is 100% at such a fast speed.

If you want to take the flash OFF camera you will have to either use a dedicated TTL lead or triggers such as the Pocket Wizards TT1/TT5. Most other triggers will limit you to your sync speed.
 
Remember the outdoor flash photographer's golden rule:

f/22 and be there. With some serious w/s. ;)

What the other guys said - but high speed sync gets severely limited at high shutter speeds and decent range. This is why you see Dave Black and Joe McNally strapping several guns together.

You can jack it up to f22 (or whatever) but then you'll need some serious flash power. You can also use an ND to drop the aperture and pump in all the flash you can get. This is why you see JoeyL marching through the jungle with a ProFoto generator on his back. A Lencarta Safari can deliver retina scorching power and a reasonably light kit.

Or, you know, wait for dark......
 
Just to jump in as I'm planning a similar shoot, would a reflector do the job better in this situation?
 
Even a powerful flash can struggle against full sun. DO NOT use an ND filter - that will cut the flash as well as the ambient!! You need to up the flash comp to maybe even +3 and test test test. It can be done.
 
Alan Clogwyn said:
Just to jump in as I'm planning a similar shoot, would a reflector do the job better in this situation?
Click to expand...

Yes.

awp said:
Even a powerful flash can struggle against full sun. DO NOT use an ND filter - that will cut the flash as well as the ambient!! You need to up the flash comp to maybe even +3 and test test test. It can be done.
Click to expand...

The point of the ND filter is not to reduce the flash power required, it's to reduce the aperture you can work at. If you can hit 1/250 f/16 then you can light to this (or maybe a stop more for drama) then drop a 4 stop ND filter in. Leave the light as it is and shoot at f4 and you'll get perfect exposure and shallow DOF. Like this http://strobist.blogspot.com/2010/06/using-nd-filters-to-kill-depth-of-field.html
 
ooor using multiple ttl ocf with high speed sync

depends whether you have portable studio flash or multiple proper speedlights
 
awp said:
You need to up the flash comp to maybe even +3 and test test test. It can be done.
Click to expand...

That's a bit of a red herring don't you think. Adding +3 won't make the flash any more powerful than it already is it'll just help with the auto metering. The OP is still going to have the same lack of power problem.

david1701 said:
ooor using multiple ttl ocf with high speed sync

depends whether you have portable studio flash or multiple proper speedlights
Click to expand...

Not much use when the OP only has one 430EX though;)
 
nor does he have portable power

either the 430 works hss on a cable or you need to buy on of the two options if you want to fight the sun.

That or use open shade/wait for the dark like John said :D
 
Thanks for the responses - yes, I'm afraid that I only have a single 430EX and I certainly dont have the funds for portable studio flash (also, I dont think it will go down too well expecting teh wife and kids to lug it about for me!)

OK, so my example wasn't a great one. I'm not necessarily shooting directly into the sun, or even with the sun behind the subject. A recent example would be when we had all the snow. It was a nice clear bright day and the scene in general necessitated a fast shutter. WHat I wanted to do was give a little more light to the subject to try and balance with the rest of the scene.

Please execuse my lack of knowledge on this - I'm quite new to flash and haven't had much practice (or RTFM!)
 
use high speed sync, basically it lets the flash fire really fast pulses which steals power (though steals less and less as the shutter speed goes up) I would tell you which button it is but I haven't got the flash on me :s

fairly easy to find in the manual though afaik the 430 manual was only like 17 english pages or something.

A good option if you're working over reasonable short distances or for fill (or both)
 
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