Flash settings

[Mick B]

I am still working out the various settings on my new Canon Speedlite 430EXII which is on my Canon 500D. Mostly I just leave it on auto and it does a great job, but I like playing around with the settings to see what they all do. Yes I do have the manual and have read it, but there's nothing like hands on.

There are a few different ways to adjust the flash output.
1 ..... In manual mode I can set it from -3 to +3 via the flash.
2 ..... In ETTL mode I can adjust it via the "SEL/SET" button on the flash, and
3...... In the camera under Flash control / Ext flash func setting / Flash exp comp and then adjust from -2 to +2.

To me they all do the same job except that in manual mode it only affects the output when bouncing the light.
Am I right in my assumptions ?

Mick.

[pollen]

I am not familiar with the 430EXII but I am not sure you have gotten it correct

Manual sets it in steps so you have 1/1 (full power), 1/2 (half power), 1/4 (quarter power) etc. etc.

Flash exposure compensation (FEC) is an adjustment of ETTL, so whether you set it on camera or flash does not matter but it should let you set the same amount. I recommend you set it on the flash unit directly only so you don't have to fiddle with the camera buttons and get confused with normal exposure compensation (EC - totally unrelated to FEC, but will affect the exposure as well).

Manual Flash is when you want unmetered flash at a particular output level, unless you have a specific purpose to use Manual Flash (e.g. in a studio environment where you need consistent light output and your subject to camera distance is not changing)

ETTL is best used as the general purpose mode. It will meter (determine the light required) for a particular scene. I generally like to set my flash units to +2/3 FEC by default when bouncing as ETTL tends to underexpose (deliberately to avoid clipping highlights)

[Mick B]

Thanks Pollen, I find it easier to make the changes via the camera as my fingers aren't made for the little buttons on the flash !

[vk2gwk]

As pollen already mentioned you can manually set the output of the flash from "full" ( = 1/1 ) to fractions that correspond with half a stop down to 1/64.
The range of -3 to +3 is the "flash exposure compensation" - same as on your camera where the range is usually -2 - +2.

With bounce flash or when using a flash diffuser you artificially reduce the flash output in a way the ETTL system is not aware of. That means that you have to increase the FEC (= flash exposure compensation) by usually 1 stop or even more (depends on the distance of the bounce ceiling and/or the kind of diffuser.

Beware when using Av or Tv (Aperture priority or Shutter priority) that the metering of the whole scene is set for the background and only the foreground subject will be "flash" metered. When I want a certain aperture (for a certain DOF) When using faster shuttertimes (in excess of the fastest sunc. speed of your camera - say 1/200 sec) you would want to activate the HighSynch button. That is useful when using fill flash with wide aperture settings.

I got to grips with my flashes by setting up various shooting situations in and around the house and taking shots with the flash while writing down the parameters (like flash power settings and distance to the subject - things that connot be found in the EXIF) and then comparing the shots on exposure.

[Mick B]

Thanks vk2, I wondered about loosing light when bouncing off a ceiling or wall and what you say makes sense. More experimenting needed. I know I should write the different settings down so I can see the differences, but I guess I'm just plain slack and think I will remember them. By the time I look at the settings on "display" I don't know where I am up to, plus it doesn't always show what I want to know.

Mick.