This blog is my attempt to keep track of some of the things I learn along the way, with my Canon 7D, G12 and accessories. All images copyright Brad Calkins, not to be used without permission (or purchase). I do not attempt to monetize my blog, other than to promote my stock photo portfolio on Dreamstime.







Thursday, January 3, 2008

Canon flash ratio with STE-2, 580EX and 430EX

I recently acquired a new 430EX flash to go with my 580EX and STE-2 transmitter. Since one of the things I can now do is balance the two flashes while still in E-TTL, I decided to do a quick test with a typical sample subject. I haven't found many examples on the web, so I wanted to post these as an example of what you can do using the STE-2 - which seems to get a bad rap on the various off camera sites compared to the pocket wizard (dg28 excepted).

The poinsettias have a similar problem to a person's face - when you use bounce flash off the ceiling, there are shadows in the areas that can't 'see' the light from the flash. This is typical of a person's eye sockets. I therefore added my second flash to hit the flowers from the front, while my second flash bounced off the ceiling. I took a series of 7 shots to go from 8:1 through 1:8. You can see how the fill flash on the leaves goes from non-existent to overpowering as I run through the ratios. Also the room in the background gets less and less lit as the front flash goes up in comparison.

8:1 (bounce to fill)

4:1
This one is getting some detail in the leaves underneath, but starting to cast shadows on the leaves as well. I had the flash to the left of the camera so this could be avoided if I had put the flash on axis, and slightly above the camera position.

2:1

1:1
1:2
1:4

1:8

Here is a quick setup shot, with the front flash shown on the couch next to my camera position. The other flash is on the end of the fireplace mantel - next to the lampshade. My exposure was short enough in shutter speed to not pick up any ambient light in the shot.

2 comments:

Prabs said...

Hi Brad - Thanks a lot for explaining the flash ratios with example shots. Very clear. Question, I guess when you started with 8:1, the 8 being from the flash on your sofa right? On your last test case, 1:8, the shadow on the leaf on the right bottom was that of the red leaf above, cause by the bounced light on the mantel. Did I get it right? I am newbie into flash photography.

John
Canon 7d, 420EX, 28-135 mm (1:3.5-5.6) IS

Brad Calkins said...

Thanks for the comment! Actually, the "8" in this case was the flash on the mantle bouncing up to the ceiling, lighting the tops of the leaves. The shadows in the bottom shot were caused by the flash shown on the sofa, which was to the left of my camera position... Because it is so low down, it actually caused shadows on the TOPS of the red leaves, which were filled in by the much less powerful bounced flash.

Cheers