Fancy doing some insect macro out in the wild and I’ve been trying out various lens solutions and lighting. Last time I did any of this I just brought the flies into the studio and this works well. See here. This time I wanted portable rig for capturing the flies in their natural environment. Here’s the first rig. A Sigma 105mm Macro with some passive extension tubes on it to give more magnification, but with the loss of auto-aperture control. Normally, with modern automatic cameras, the aperture diaphragm is wide open when you are looking through the finder, and only stops down to the aperture you dialled in when you take the shot. This means there is plenty of light to see and focus the subject by. Without auto-aperture control, you either have to open up and stop down the aperture using the aperture ring manually (and in doing this you’re mess up your focus) or you need to look into the darkness and attempt to focus the subject with the aperture stopped down. As you can imagine, the success rate isn’t high :-/
For the light I jammed on a small soft box, which has enough surface visible to the subject to cast some light on it. Most of the light is lost though, and it’s a bit harsh. I’ve switched out the soft box for the Rogue Flash bender XL with the soft box attachment. This gives a good wrap around light and the best bit is that of course, you can bend it, so if you want more light on the right or left you can bend the appropriate side down, or bend the far edge down for some more backlight etc. The subjects will be around 40mm from the front of the lens (or back of the lens in this pic as it’s reversed :P) so from that position it’s a really nice soft light.
I’m just using the flash on TTL, with the camera in manual exposure, 1/250th of a second at around f/8 to f/16. I’ve left auto ISO on for these as well. As you’ll see below, this means more or less ambient in the scene depending on the magnification, with an almost black background for the higher magnification shots, as the ratio of distance to camera (and the light) between subject and background increases (and so the light falloff is more pronounced).