I’ve been bitten by the macro bug and want to know the difference between a macro flash and a regular flash?
BRIAN SAYS… As you’ve discovered with macro, you are often working with the aperture closed down, and that limits the light, coupled with a fast shutter speed to avoid camera shake or subject movement, the option is more light or higher ISO. Using flash is a good solution since the very short duration of flash also freezes movement for sharper shots. Since macro subjects are close to the camera and lens, then the light needs to be similarly close, and then you have a range of options.
The traditional macro ring flash mounts around the end of the lens, and is great for providing flat even light to subjects close to the camera. Canon’s macro ring flash MR-14EX II has two separate tubes that you can control the ratio of for a little more shaping to the light. Ring flashes have little power, but that’s because they only light subjects close to the camera. At f/16 and ISO100 your max working distance with the flash would be just under a meter. What most people don’t realise is that the ring flash can also control other Speedlites, so if you want to illuminate backgrounds that is possible, and all of this can be done with auto exposure.
Another option for larger subjects, is to use a regular Speedlite with a small softbox to create a soft light that you can handhold or use on a small stand. I use a 22cm square softbox for flowers, as it helps to illuminate the scene rather than a specific bloom. You’ll need a regular Speedlite, something like the 430EX III-RT is a good option, and either use a dedicated off-camera cable like the Off-camera cord OC-E3, or a Speedlite Transmitter ST-E3-RT to control the flash over radio wireless. With this last option I put the camera on a tripod, and remotely release the shutter from a button on the Speedlite.