Metering Question

[warrior6901]

This one will probably sound dumb, but if so it won't be my first one! I understand you can get the camera settings measuring ambient light and then you get other settings when measuring the flash.

Question: How do you combine these for the final settings for the pictures? Are there some ratios to use, a chart for final compensation, or are we still in trial and error mode to find the best combination?

Thanks for the time for a newbie.

[Titus213]

It depends on what sort of lighting you are using. With the camera mounted EX flash I generally meter the scenes ambient light with the camera, put the flash in ETTL mode and adjust the FEC to achieve what I'm looking for. Use the histogram to get dialed in. Unless you are using a separate flash meter there is no way to measure the flash for settings that I know of.

If you are using multiple flash units it's a bit more complicated. Have you gone thru the flash stickies on this forum? There is a ton of very useful info there.

http://photography-on-the.net/forum/showthread.php?t=138907

http://photography-on-the.net/forum/showthread.php?t=138912

[CanonCam]

I'm not 100% sure what you are asking, but I think this is the general area you are after. If not, just say so.

There are indeed two exposures for a flash photo, one the camera makes for the scene (or background) and one the flash makes for the subject (or point of focus). If the flash is set on ETTL, this one will be done automatically. Set your camera up as you would for the background (assuming you are outdoors?) and the flash will take care of the subject so long as that subject is within the flash range. Indoors, I set my camera up like so: 1/125 shutter speed, ISO 100 (or 200), and my aperture at 5.6 or so. Your meter will say HEY! but once the photo is taken the light from the flash will fill in what the meter sees is not there (light). From there, I look at my histogram and adjust accordingly.

As for a chart, Hopefully Curtis will chime in here as he has a great calculator for this and also DOF, but I don't currently know the link. Hope this helped a little.

[taygull]

Studio or on camera? Indoor or outdoor? Bright light or low light? Fill or full exposure?

I ask this because I do different things depending on what I want to happen.

When indoors I use shutter speed to control the amount of ambient light I want. I almost always use a shutter speed of 1/30th - 1/50th when shooting indoor events and bounce the flash. This gives me a combo of both.

[warrior6901]

Thanks folks.

Studio 3 AB setup...AB 800 with Softbox for main light, AB 400 with umbrella bounce or shoot through and AB 400 for back light. I don't have or am not using hairlight at this time.

Any additional info will be most helpful. I will check the links and the stickies.

Thanks

[taygull]

Meter for your subject and then watch as you adjust your shutter speed from your max sync speed of 1/200 or 1/250 all the way down to 1/30 (use a tripod).

Watch how your ambient light will increase and decrease but your "flash" will stay pretty close to the same.

[Titus213]

Studio is a different animal than camera mounted. There are lots of folks here who will jump in and help but you should have a meter if you are using multiple lights - if nothing else it will make the setup much easier.

I just picked up a Sekonic L-358 light meter and it will indicate what percentage of light is ambient and what percent is flash - at least from my cursory examination of the manual. The real test will hopefully come this week.

[warrior6901]

After much reading/research, I should have the L-358 tomorrow. I am looking for some of that stuff that we find out on our own with T/E and isn't written in the manuals.

Thanks