Quote Originally Posted by Ralph


Hi guys! I got myself a cheap flash diffuser (probably a Sto Fen clone) for my 580 EX II. It comes in three colors, white, blue and yellow. This seems to be a newbie question, but how do I use them? Or rather, how do I use them properly? I've read some that it should be positioned to a max of 45 degrees towards the ceiling. What are the strengths and weaknesses of using this diffuser aside from a few light loss?





Thanks!
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Ralph,


I have one stofen diffuser and never use it. I find that when shooting indoors bouncing the light off the wall and ceiling creates much more natural looking shots. I use some sort of gel usually 1/2 CTO or 1 CTO to balance the color temperature of my flash with the color temperature of the incandescent lights in the room. This is getting harder now do to CFL technologies. You now need to also add a 1/4-1/2 pale green gel to color deflect the green associated with flourescents. But this doesn't quite answer your question.


The trick to good flash lighting stofen diffuser at 45 degrees or bounce is to use a high ISO. I shoot most of the time at ISO 800, f4, 1/60th to 1/125th. Photojournalists use stofens not to soften the light but to reduce the harshness and fill in shadows. For instance, when shooting at an indoor event, stadium, church, large hall, press conference. There is usually enough light to properly expose at ISO 800-1600, f2.8-f4.0,1/60th to 1/200th but the shadows around the eyes from overhead lighting make the subject look really sick. What you desire todo is to flash in enough color balanced light to fill those shadowed areas and make the subject look like a healthy human. That is why you see so many photojournalists using it at 45. It is also off-axis and reduces the red-eye effect. It also brings out more color and makes skin tones look better. Last but not least, it improves sharpness.


Try experimenting with manual mode and flash compensation. Take a few test shots until the subject and environment are around a 1/2 ev under exposed. Optimum settings are ISO800, f4, 1/60th. Now, turn on the flash, set flash compensation at 0, aim the flash sideways and behind you a little at the corner of a wall/ceiling. Take a few shots. Aim your flash in different directions and note the effect. If you don't get enough light from the bounce try turning up the flash compensation a little until you get enough. If too much, do the opposite.


Repeat this type of procedure in a large hall using the stofen a 45 degrees. There, you may have to comp down a little.


The very important rulesare:


1) Aperture controls the exposure of the light from the flash regardless of shutter speed. Read this 4 times


2) Shutter Speed controls the level of ambient light. slower shutter more ambient, faster shutter, less ambient. Read 2 times.


Experiment with these two rules and you will see your flash photographing greatly improved.


I posted this just recently on the pets thread. Itook it using bounce flash technique.





Canon EOS 5D, EF 28-70 f2.8L @ <span class="nowrap"]f/4&amp; <span class="nowrap"]70 mm, <span class="nowrap"]1/60, <span class="nowrap"]ISO 800, <span class="nowrap"]Flash (1/2 CTO), bounced against the wall ceiling camera left. I'm not sure but flash comp was probably around +1/2-1. My Quantaray 9550 doesn't have near the power of a 580 EXII.


<span class="nowrap"]Hope this helps......2 []