Am I doing fill flash right?

I've been reading about fill flash lately (after acquiring my 430ex) and want to learn how to do it correctly. I often see photographers using their flash in bright daylight and always wanted to know why they did it. I have a few questions I hope you guys can help me answer.

1.) Fill flash is used to "fill" in the shadow areas present in a subject, correct?

2.) Is the difference between the fill flash and the regular "ambient" day-lighting just the flash itself? For example, would I use the same Aperture, Shutter Speed & ISO to achieve a correct exposure, and THEN add a flash to it?

3.) How much power would a fill flash usually require in the daytime? Would ETTL be better than Manual flash settings?

4.) Would using Av mode be more helpful in this situation, since it will already have "calculated" the correct exposure for you?

This picture by *Knowledge*, posted in the 35L Lens Archive, is one of my favorite pictures here on POTN. The lighting was incredible, and I want to learn how to replicate this type of light:

https://photography-on-the.net …p=10247188&post​count=4554


I took some test shots and am hoping to get your opinions on whether I'm on the right track or not. Thanks!

Ambient:
Av Priority @ f/2.8
1/50
ISO 200

looks to be a bit too much to me, the subject is exposed a bit too much compared to the background

If you already have correct exposure, then add some by using a flash, you'll get overexposure. Hence you need to reduce the ambient exposure a little, like one stop, and then add that loss with the flash.

But if you use fill flash to light up a face, that's in the shadow, then that face is likely to be at least one stop underexposed already, and the fill flash will not reach the background, so there will be no overexposure there either.
So whether you'll need to reduce exposure of ambient light or not depends entirely on the situation.

If you use the camera in an automatic mode, say Av, then turn the flash on and off, you'll often see that the camera will automatically reduce the exposure of the ambient when you turn on the flash.

The fill flash in the image above is obvious. If you want it to be, fine. If not, reduce flash exposure a stop or two.
You can use E-TTL for fill flash. Often you only want to fill a certain smaller area, so using FEL (and thus spot metering the flash) is often a good idea.

^^^ Thanks a lot paradiddleuke & apersson850. When using fill flash, one would have the flash pointed directly at the subject, correct? Would a diffuser of any sort benefit?

Would you then recommend sing Av for fill flash, since the camera would automatically reduce the exposure of the ambient (but then I would also need to probably do a -1 FEC or so?) if it detects the 430EX being on? Or would using Manual result in more "accurate" exposures, since I would be controlling everything?

Well, this picture is already pretty good in terms of exposure already. If you want to lift the shadow a little, then use 1/128 and may be a diffuser. The second picture to my taste is about a stop or two over exposed in terms of flash filling. The power setting of the flash is relative and is subject to change mainly depends on ISO, aperture and subject distance,but when i need something that needs proper exposure, I usually don't trust the camera setting, so i do set my power setting myself. Try to learn a little more about light and i'm pretty sure it'll help you a lot!

Say you are shooting a girl sitting inside, with a window behind her.
In such a case, I would most certainly use manual on camera (M) with spot metering. I would set the camera to give correct exposure for the light outside the window. No reductions for the fill flash, since it will not reach out there anyway.
Then I'll use E-TTL II and take a photo of the girl. If I have a reflector, maybe a wall behind me, I'll use that. If there is nothing, I'd have to go straight on.
With a reflector, I'd try to use no FEC (Flash exposure compensation) to see what I get. If forced to aim the flash straight on, I'd set -1 FEC, to avoid too much "high beam effect".
If there is time, I'd then look at the image and the histogram on the camera's display, to see if it seems reasonable or will need any change.

If you can direct the girl, then it's easier, as you simply tell her to stay put whilst you arrange reflectors, umbrellas, softboxes - whatever it takes to get a nice picture. But I'm usually more into candid shooting, so I'm not too used to that kind of arrangement.

I would have to disagree about the comments of the second/fill shot being over exposed. I am not seeing that. What I AM seeing is that the second shot (with the fill flash) looks too 'flashy'. What is contributing to this 'flash' look and making it look too snap-shot-ish is that now the lighting on the subject is flat and we are now getting a sharp/harsh shadow under the chin. By flat lighting I mean that the subject is too evenly lit. This is simply what happens when a subject is lit on the same axis as the camera. This is usually bad because shadows help our brains interpret shape and so when there a little or no shadows the image becomes less 3 dimensional looking and more 2 dimensional.

In your first shot you can see even a little bit more light coming from the window on one side of his face and even though the rest of his face is needing a little more light this shot depth-wise works better because of the natural ways the light is falling on him. Also look at the image you linked us to... see how there is more light on one side of the subject than the other? This too is a good example of modeling the subject with off-axis light to create natural shadows to help our brains decode shape.

So the way you do this is to bounce the flash off a wall, ceiling, and even a window as long as the surface you are bouncing off is neutral in color (or get the flash off camera). This will do two very important things, it will create off-axis light and it will also soften the light which will give you softer, less harsh shadows and make the light look less 'flashy' and more natural.

So, I see that in your second shot that the fill flash exposure is just fine, not over exposed. It just needs fine tuned to make it look more natural.

Yes, you are right in trying to set the camera to expose correctly for the ambient light correctly most of the time and then using the flash to fill the shadows on the subject. This also helps create a natural looking image.

As far as what settings to use when trying to use fill flash here is how I go about it... (This is for fill flash only, totally different when using many lights to create the environment totally with multiple flashes)

Indoors with low light and the flash on the camera I set the camera to manual mode. I set the shutter to something reasonable based on the situation. For a static subject like someone sitting still for the camera I typically use anywhere from a 1/60 to 1/200 shutter speed. I set the aperture typically as wide as can but still get in focus what needs to be in focus. I then dial the ISO up or down and look at the light meter in the camera. I usually like to shoot so the camera is underexposing the ambient by about one stop. This darkens the background a little and helps the subject pop more... but not so dark that it creates bad harsh shadows from the flash hitting the subject. I may even dial the shutter down slower depending on the situation. I start with the flash in ETTL and use flash compensation to tweak the power of the flash. I use ETTL most of the time like this because I may be moving around even if the subject is not and when I move the distance of flash to subject moves and anytime this happens ETTL can get you to a proper flash exposure faster than dialing it totally in manual... of course this depends on how much you or your subjects are moving about. But I always try and bounce the flash off a wall or ceiling for reasons already mentioned.

With a total static situation where camera/flash and subject are always the same distance it would be better to dial the flash in manually. That way once you get it there it will consistantly deliver consistent results.

I hope this helps...

Ron