Canon 430EX II Speedlite questions

Bluepoole · Aug 21, 2009

Hi all

With regards to my Canon Speedlite, I would like to ask the following questions:

What are effective techniques to minimize shadows being cast against a wall behind your subject, when using the flash?

And then also, I noticed that I get much better results when I use the "manual zoom" to cover the range of the flash, as opposed to leave it on auto (with manual zoom, the value used is equal to the focal length of the shot). Any reason why? Sometimes it is difficult to adjust the value manually when taking a lot of shots in succession.

Another issue I have noticed, which I suppose could be related to the second question, is that when the zoom of the flash is on auto, my subject is much more illuminated at the telephoto end of the lens, as opposed to wide angle shots. But my distance from the subject is the same, so I don't understand why? Especially because the value in metres of the coverage of the flash is higher (with other words, stronger flash?) with wide angle shots.

Comments would be appreciated!

musicaleCA · Aug 21, 2009

Bluepoole said:
What are effective techniques to minimize shadows being cast against a wall behind your subject, when using the flash?

Bounce the flash so that the shadows fall out of frame. The easiest thing to do is point it at the ceiling, but you can also use walls, or anything else big and will give a soft reflection (avoid mirrors and windows).

Bluepoole said:
And then also, I noticed that I get much better results when I use the "manual zoom" to cover the range of the flash, as opposed to leave it on auto (with manual zoom, the value used is equal to the focal length of the shot). Any reason why? Sometimes it is difficult to adjust the value manually when taking a lot of shots in succession.

If you leave it alone, and have the flash head pointing forward, the flash will zoom to waste less light as you zoom the lens. It should also detect if you have a crop sensor and compensate accordingly. Not really sure why you're seeing better results; I generally bounce my flash so I have the set it manually anyway. The flash head's zoom is also a useful tool for lighting off-camera.

Bluepoole said:
Another issue I have noticed, which I suppose could be related to the second question, is that when the zoom of the flash is on auto, my subject is much more illuminated at the telephoto end of the lens, as opposed to wide angle shots. But my distance from the subject is the same, so I don't understand why? Especially because the value in metres of the coverage of the flash is higher (with other words, stronger flash?) with wide angle shots.

Because the subject is filling more of the frame, the ETTL system will see the frame as being much more underexposed, and try to (over) compensate. (That was put very, very simply. The actual issue is a wee more complex.) If you're outside, dial-down the ETTL EV comp to around -2 or -3 stops.