Metering for Ratios ... ??

[bigdazzler]

ok this is the shot set up ...

1 strobe at high right of camera 45deg , 1 fill reflector on short side of models face to soften shadows. I want a ratio of 4:1.

Is this the right way to go about metering the shot,

Set SS to max sync, and ISO to 100.

1. Meter key light at models chin and obtain working aperture.
2. Take a meter reading on shadow side of models face and place reflector required distance from subject until reading is 2 stops under key light.
3. With key light on and reflector in position, take a final meter reading at models chin and set camera aperture.

I ask becasue i wanna get my head around metering for reflectors and controlling the light that they add to a scene.

Am I on the path to one light awesomeness yet ?? :D

[BBW]

Bigdazzler,

You don't mention the type of meter you intend using: The technique will vary according to kit.

The method you describe sounds like you are using an incident light meter. If it has a choice you are better off using a flat white disc diffuser rather than a spherical diffuser for setting lighting ratios - that way ONLY the light from the source affects the reading.

Once you have established the ratios you replace the spherical diffuser to take the actual exposure reading.

I might add that an actual exposure reading can be made with the flat diffuser IF the subject itself is flat - like copying art work.

If you don't have a flat diffuser than the spherical jobbie will do but you may need to shield it from unwanted sources.

Using a reflected light meter would not offer sufficient precision of target area in my opinion unless it was a 1º spotmeter, in which case: read the lit area, read the filled area and work out your ratio from there.

Hope this helped.

[bigdazzler]

Thanks mate .. and welcome to AP :D

There were a couple of the regular flash gurus that I thought might respond (slackers :p) but seems you got in first .. :)

Yea Ive got a Sekonic L308S flashmate .. it has both a spherical and flat disc diffuser.

So youre saying im better off taking the initial readings from the key light and the shadow/reflector side with using the flat disc and then slide it back over and take the final shot reading with the sphere ??

[I @ M]

I haven't done much with reflectors at all Darren but when working with 2 or 3 lights I start with the shutter speed and iso that I want to use set in the light meter then check each light individually sarting with the key light adjusted to the output that gives me the aperture ( or as close as possible ) that I would prefer to work at. I then work on metering and adjusting the power levels of each additional light from there to obtain ratios.
Once they are set, rechecking with all lights operating usually confirms what I started with.
I'm enjoying the learning curve as well and when a particular way works out I try to remember the parts that went into the set up and apply them again at a later date. Surprisingly, many things that work well are the ways that have been described in numerous books and articles on the www but it was fun experimenting and THEN reading how to do it. :D

[bigdazzler]

Im really trying to keep things simple at the moment. One light, one reflector. I read something on the interweb this morning that gave me new perspective when it comes to reflectors. I never considered them an actual light source, or the need to meter for them. It seems so obvious now becasue that is their job, to ADD light :o

So Andrew, you prefer to choose your aperture first, then adjust flash output to suit ?? I guess you can control your desired DOF more easily that way, rather than blasting your flash on full power and getting whatever aperture the meter tells you.

For eg .. say you want 1/125th , ISO 100, and for nice portraity DOF you want f5.6 or even f4 .. you would then start at say 1/2 power on your key light and chimp away with test shots adjusting output until your meter is telling you 5.6 ?? And so on and so on for the additional lights .. say a fill light at 2.8 and maybe a grid spot on the hair f8 ..

am i on the right track here ??