Originally posted by hll (snip) i don't use a translucent umbrella. (snip) is aiming top something right or??? do you aim to the center???
Yes, the flash unit is generally aimed towards the center of the umbrella. The image in your first message shows a translucent shoot-through umbrella, which is why everyone is thinking in that direction. Regardless, when bounced into a silver reflective umbrella, you can expect to lose from 1/3 to 1/2 of the light output (perhaps even more with soft reflective types). Again, hard to say exactly since no two umbrellas are identical. And, again, larger umbrellas consume more light than smaller ones.
One last possibility. Make sure the flash unit is far enough away from the umbrella interior. A portable strobe, versus a typical large studio strobe, throws a comparatively narrow beam of light. As such, the flash unit should be far enough from the umbrella interior to allow that light to spread some before hitting the umbrella. Any closer and the flash unit itself may actually block a good amount of the light bounced back.
I've run out of suggestions at this point. Therefore, if nothing said so far provides a satisfactory answer, the only option left is to expand the discussion greatly to include mounting (light stand or other), location (how far is the umbrella setup from the subject and where are you aiming it), metering (what are you using to meter the light and set exposure), your subject (what are you trying to take an image of), and so on.
stewart
By the way, and certainly off-topic, I once lived (two years) near Istanbul (across the sea near a town called Yalova) many years ago. The Sea of Marmara and surrounding countryside is beautiful and Istanbul itself is an very interesting city. I'm looking forward to a return visit some day.
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