Bounce Flash and CF-14

[craig_dumesny]

I have been using the Canon 1V and 550EX Speedlite combination for

bounce flash indoors (living rooms and bedrooms) and have noticed an

inconsistency in a number of my exposures, mainly that some appear to

suffer under-exposure of peoples faces. I tend to set the camera to

M-mode at around 1/30th and f/5.6 with the 50mm f/1.4 lens, to

achieve a more natural ambient like look. I am also placing the red

box on their face to focus and establish exposure and then

recomposing to take the shot.

 

I believe what has been happening is that the auto flash reduction

has been kicking-in due to the ambient light present at the time. If

this is indeed what is happening (and enlightenment here would be

appreciated) should I disable this feature using CF-14 or perhaps

dial in +1.5 on the flash?

 

Regards.

[jay_.]

I've disabled the auto-fill-reduction on all my bodies thus far. I don't like a camera to try to think for me.

[gary_labate]

You should use the FEL when the red focus box is on their face and then recompose.

 

When you recompose without locking the flash with the FEL button the flash will take an exposure reading at a different spot in the new recomposed scene. This may cause under/over exposure on the faces but the spot where the flash took it's reading when you pressed the shutter release will be exposed correctly.

[craig_dumesny]

I think I'll try to disable the auto function first...and then test, test, test.

 

Thanks for the early replies.

[zlatko]

When you place the red box on the face, you establish ambient light exposure but not flash exposure. Flash exposure is being set after you recompose. So at that point the red box may be on lighter or darker clothing or on the background. The only way to set flash exposure before recomposing is to use the FEL button on the face and then recompose. I would also disable auto flash reduction, just in case that is contributing to the problem. Finally, if FELing on a light-skinned face, add about +1/3, +2/3 or a full stop in flash exposure compensation; otherwise set it to 0.

[paulo bizarro]

Just another thought: I may be wrong, but I think that CF14 only kicks in when the ambient light level is high enough (refer to the camera manual, it has a graph of that somewhere), so I am not sure it applies indoors.

With bounce flash, the light is reflected from above into the subject, effectively shadowing the faces of people. This is where a flashgun with a second tube comes in handy, like some of the Metz's. For indoor shots, I usually use Av mode, disable CF14, and dial in +1 and 1/3 FEC.

[paulo bizarro]

Uuups! In my previous posting make that -1 and 1/3 FEC...

[Ken Katz]

Fill flash reduction should only kick in at light levels above EV 10, therefore it does not have any effect on indoor flash photos.