A reader recently posted a comment on one of my earlier posts, saying he couldn't get his Phottix Aster (PT-V4) wireless flash trigger to trigger a flash when using his Canon 450D in liveview mode.

While I have done a lot of off-camera flash photography, I had never tried triggering a flash with my Canon 50D in liveview mode, and had no idea if there were any limitations.



Armed with my Canon 50D, a Canon 580EX flash, a few wireless flash triggers, and some PC sync cables, I did some testing in liveview mode.

Here are the results:

50D with Phottix Tetra wireless flash trigger	fails to trigger flash
50D with Phottix Aster wireless flash trigger	fails to trigger flash
flash directly connected to 50D pc sync socket	fails to trigger flash
50D with 580EX flash on hotshoe	successfully triggers flash
50D with Canon ST-E2 on hotshoe	successfully triggers flash

A quick look in the 50D manual provides some insight. It says the following about Silent Shooting mode when using liveview: In other words, with a Canon flash on the hotshoe, the camera will automatically change the Silent Shooting mode to "[Disable]" to ensure it can fire the flash. However, if a non-Canon device is attached to the camera (ie, a third-party flash trigger, or a PC sync cable), the camera will fail to trigger the flash if the Silent Shooting mode is not set to "[Disable]".

On the Canon 50D, "Silent Shooting" mode can be set in the "Live View function settings" menu.
After changing the Silent Shooting mode to "[Disable]", the 50D could successfully trigger a flash with the Phottix Tetra and the Phottix Aster while in liveview mode.

When taking macro photos, you need plenty of light on the subject, to allow a reasonably large DOF (depth of field), yet keeping a reasonably fast shutter speed, and a low ISO. As a result, ambient light is typically insufficient, requiring the use of a flash.

However, using a bare flash will result in harsh lighting with harsh shadows, so it's important to diffuse and reflect the light to create a more pleasing photo.

This post provides details of the very cheap homemade reflector that I use for macro photography. Note that I can't claim credit for the idea, but I first saw it here on flickr.

With Australians being forced to switch from incandescent globes to compact fluorescent lamps (CFL), it's important to be aware of the fact that CFLs contain mercury. Breaking a CFL will release this mercury, and there are some significant health and safety issues associated with cleaning up this mercury, as well as disposing of CFLs.

On February 2007, the Australian Federal Government announced that incandescent light bulbs would be banned in Australia by the year 2010. Apparently that makes Australia the first country in the world to announce such a ban (ref 1, ref 2).

The primary reason for this ban is to encourage the use of compact fluorescent lamps instead of incandescent globes, as CFLs use approximately 80% less electricity, thus reducing Australia's greenhouse gas emissions.
Apparently by 2015, the switch to CFLs will reduce our greenhouse gas emissions by up to four million tonnes per year.