Fill flash metering

Hi all,

Quick question:

If I want to use fill flash for portraits would I be better to spot meter the face, or meter (spot or otherwise) the background and the fill in ettl dovthe rest? Would that be different if a bright sunny day, or indoors.

Thanks in advance

David

Depends greatly on how you are working. What mode you are in. I almost always use my flash in M mode and let ettl do the fill. Depending on what look I'm trying to achieve I may slightly underexpose the back and use the fill to hightlight the subject a bit. But if I were just in av and wanting fill I just meter (whichever mode you like) the scene and then let the flash fill using ettl and a bit of negative FEC.

Metering the face...if you first spot meter the highlight area of the face, then meter the shadow area of the face with the fill from flash, that certainly does provide the relative reflected light contrast ratio.

You could also incident meter the ambient light, then incident meter the flash, using the flat disk t measure the light falling upon the subject from the two light sources, and that tells you the relative intensity of the sources -- but fails to tell you the reflect light contrast ratio resulting from the overlapping of the two sources on the subject.

Thanks both. I will most probably be in av for the most part, although some m. So Wilt, are you saying I'm best to spot meter the highlighted part of the face and let ettl fill the rest?

David

beegeeboy wrote in post #12354096
Thanks both. I will most probably be in av for the most part, although some m. So Wilt, are you saying I'm best to spot meter the highlighted part of the face and let ettl fill the rest?

David

That only tells you the relative brightness of one side of the face vs. the other...it does NOT give you 'proper exposure' since the skin could belong to a black man, a tanned Italian, a winter palored Norwegian, or someone else! Proper exposure is measured with an incident meter pointed at the lens, or with a 18% gray card filling a reflected light meter's view. And that is the flaw behind ETTL simply measuring what is in the frame...metering biased by subject brightness unless you dial in FEC as appropriate.

I just set the flash to ETTL and then dial the exposure comp down to -2 or so. Chimp the shot and adjust as needed.

Ok guys cheers-more to think about!

David