To much flash

[Graeme Buckland]

My problem is that I don't use flash that often but when I do I seem to blow the faces off of the people that i am photographing.
Example, I want to use the flash just as a fill flash, I just blow the faces out and end up with a very over exposed image.
I have the canon 580 flash (new one) on the canon 5D, i had the flash set at at -1 compensation and the camera was on manual.
Can someone please try and put me on the right track for settings as I have to take some photos tonight at my wifes birthday dinner

[MarkChap]

Graeme,
I am thinking that maybe have the Camera on TV/ AV as the camera will use the flash for fill.
If you are having the camera on manual maybe it is trying to use the flash as the primary light source therefore even with -1 compensation it is still belting out too much light for your needs. Although if you are -1 compensation I wouldn't be thinking you would get too much light unless you are really close ??

Drop the flash to manual as well and dial in the amount of oomph needed to achieve the result.

Guide Number / Distance = Aperture At 100 ISO
Or for fill, set your exposure on camera and then set the flash to 1 stop below that.

Assuming a fairly constant distance to the subject and constant ambient light this would probably give the best results.

Ambient Exposure = 1/60 f4 ISO 400
Set Flash to about 1/16 power (A very quick and dirty calculation) At 24mm Zoom
Maybe even down to 1/32

[latino]

If your serious about this type of photography I would invest in a decent light meter. They work wonders just take a test flash shot and the device will tell you what setting to use on your camera.

The advice given above will also guide you in the right direction.

Just my 2 c

[Tannin]

Graeme, let's try this the easy way. There are two issues you need to deal with:

(1) flash "focus". Just the bare flashgun mounted on the top of your camera in the normal way will often produce harsh highlights on the foreground subject, even when used only for fill flash. There are three ways to deal with this: (i) use a diffuser - the slide-out one built into the 580EX II will do, though there are plenty of others available third-party, or you can make your own, or you can bounce the flash (effectively using (e.g.) the wall as your diffuser; (ii) use an off-camera bracket to get the flash coming from slightly to one side or above; (iii) dial back the flash power even further. Obviously, there is nothging to stop you mixing and matching these methods.

(2) Flash exposure. The Canon flash system is very simple and easy to use once you understand the basic working methods. There are actually two systems.

If you use manual exposure, the flash tries to provide however much light you need to expose the subject corectly. It essentially assumes that all of your lighting is coming from the flash unit.

If you don't use manual exposure - e.g., if you are using aperture priority - then the flash system assumes that you want fill flash. Exposure calculation by the camera ignores the flash; it calculates correct exposure simply by looking at the ambient light. The flash intensity is automatically wound back by a stop or two. The idea is that you simply shoot normally (as if you were not using flash at all) but you get some gentle fill flash. In practice, my experience suggests that you need to wind on extra -ive FEC, over and above that provided automatically. Somewhere between -1 to -2 stops seems to be about right most of the time - we are trying to avoid that "flash look", so we just want a subtle bit of fill.

So there are really two main methods:

1: Expose manually for the bright background; let the flash figure out how to expose the foreground. Dial in some FEC until you are happy with the result. This sounds complicated and difficult, but in practice you soon find that you develop an eye for the right amount of FEC to use for varying shots in any given session.

2: Use aperture priority to expose the sameway you would without the flash; wind the flash power back with -ive FEC to a level you are comfortable with.