For those of us who shoot with off-camera flash while using a light modifier such as an umbrella or softbox, we’re bound to encounter the issue of having the flash not on axis with the modifier. Oftentimes, the bracket that holds the flash and modifier together are separated by at least 4-6″ of vertical space with the flash firing downwards at an angle towards the umbrella.
If we’re using a large modifier, such as a 60″ umbrella, the problem is less pronounced, or if the flash is far enough from the area where the light will be reflecting on. However, with smaller (<40″) umbrellas, the discrepancy of light hitting the top and the bottom of the umbrella will be quite visible.
I’ve found a cheap (relatively) way to line up the flash so that the light will be bouncing off the center of the umbrella, instead of on the upper part of the umbrella only by using mini ball heads.
Here’s our main problem, with the flash standing tall on top of the umbrella holder, we can see that there’s more light hitting the top part of the umbrella, causing more light spilling on the top, while more light reflecting at a downward angle from the umbrella.
Note the light falloff on the top wall area versus the lower part of the wall.
We mount the mini ball head onto the 1/4″ stud on the light stand then mount the flash (in this case, the flash trigger receiver) onto the ball head then straighten the flash horizontally to the same axis as the umbrella pole.
We can now see how uniform the light pattern is when it hits the reflective surface of the umbrella.
Now compare the reflected light pattern of a horizontal flash position versus the image with the flash standing upright.
Notice how uniform the reflected light appears and how the top and bottom spill light on the edge of the umbrella is better controlled.
If you’re using a cold shoe mount umbrella/flash holder, you can pretty much do the same thing. The receiver below is mounted on a cold shoe, which is then clamped onto the umbrella/flash holder.
The results are the same.
We do have an issue of the flash being much closer to the umbrella now, also known as the umbrella being “choked up”. The light source became smaller and less efficient with this arrangement. In order to counteract that, we can flip down the diffusing panel of our flash or use a diffusing cup while making sure that our flash head is set to its widest setting (usually 28mm).
This is the “cheap” and easy way of doing it. The mini ball heads cost US$5 each brand new from eBay (free shipping), and they are more than enough to hold the weight of your flash. A side benefit of having a rotating ball head is it also makes adjusting the flash settings easier without lowering your light stand too much, just loosen the head and turn the flash towards you.
I will add some sort of a foam material underneath the flash head in the near future so the weight of the flash is also distributed to the shaft of the umbrella instead of just the hot shoe.
Now if you have the tools and skill to make a horizontal bracket, then all the better, you can move the flash further back from the umbrella and have more control on the light pattern of your flash to maximize efficiency. Here’s a great DIY page from DIYPhotography.net for you to try rigging a bracket at home. Good luck and do share what you’ve come up with! :)