Lighting with Sigma 180 macro

[ltlredwagon]

I have a Canon 20D, Sigma 180 Macro and Sigma 1.4x teleconverter. Looking for best flash setup for photographing butterflies. Appreciate any advice/recommendations.

 

[Derrel]

A few summers ago, I used my Sigma 180 macro with a small, roughly 5x7 inch air-filled softbox as my diffuser, to photograph swallowtail butterflies. The softbox I used was made by Photoflex, but there are very similar ones made by LumiQuest, as well as other manufacturers. You can use this small softbox with a flash located on the hotshoe, or with the flash connected to the camera with a TTL remote control cord, and the flash held off to the side and above in either your left hand, or by an assistant, or on a flash bracket setup.

At close distances, the flash is very powerful,and one trick you might learn is that dialing the flash down in power gives ultra-quick recycling,and also shorter flash durations which will stop motion pretty well. Another thing to note: you can use the magnification scale on the Sigma 180mm lens as a rough guide to the exposure in f/stop that is needed at the different magnification ratios on the focusing scale.

THink somewhwrre in the 1/4 power to 1/8 power manual flash levels for butterfly close-uops at very close distances, at f/13 or so. The Siggy is pretty good at f/13,and that will help you to get a good background expousure during the daytime during the summer months. Set the camera shutter speeded to its fastest flash synchronization speed, often 1/200,and that will handle most of the daylight in the background.

 

[NateS]

I'm with Derrell on this one. I shoot a 180mm macro exclusively and I have a roughly 3.5 x 5 inch softbox I use...now I manage to make it work but I have it setup and swiveled forward past the lens by a good 3-4 inches which is a bit of a pain. A 5x7 softbox would give much nicer light and allow more flexibility with placement. 5x7 is actually on my shortlist.

 

[ltlredwagon]

Thanks very much Derrel & Nate. I'll follow up on this. Bob

 

[Overread]

1+ to what Derral and Nates said as that is my setup as well (though I use a 150mm instead of 180mm but its pretty much the same with regard to macro). I tend to find that auto flash tends to be pretty good for most macro work, though do expect to use some flashexposure compensation from time to time. I also make use of the FEC button (the * button) to fix the flash exposure based on a bright/reflective point on the subject to try and preserve highlights.

Manual flash will work well and for macro (where the flash is the main light source) exposures can be fairly constant - however do keep an eye on the surroundings - moving from shade to open sunlit subjects will affect things.

Also a point on ISO - if you keep your ISO low (100/200) most of the light will be from the flash when you use small apertures (eg f13) however if you raise the ISO up to say 400 or 800 even though you are still using flash for the majority of the light you are allowing more natural light to factor into the shot. This can be used creatively if you so choose whilst also letting you remain shooting handheld - of course you sacrifice some quality as you shoot with higher and higher ISOs. Ideally the best way to let natural light into the shot is to use a tripod/support and shoot with a slower shutter speed and less/no flash component.