flash usage?

[mknabster]

I have a G6, and I was wondering what would a flash do to enhance a picture? I was recommended to get the 420EX. What type of photographs would using this one be good for? To put it in simpler words, could you guys just give me a whole description about flash usage?

[HJMinard]

There's a lot of territory to cover in your question, but in general you utilize a flash when there is insufficient natural lighting to achieve an acceptable shutter speed. An external flash like the 420 is more powerful than your camera's built-in flash (allowing sufficient lighting at further distances), and it also has the ability to bounce the light off of ceilings or walls to reduce shadows and harsh direct light.

A flash can also be utilized for "fill" lighting even when there is sufficient natural light. For example, an outdoor portrait with the sun overhead will leave eyes and other facial features shadowed ... using some fill flash lightens up those areas and brings out detail while also adding a nice "catchlight" to the subject's eyes.

If you're using your G6's built-in flash very often, you'll be amazed at the difference in lighting quality that a good external flash will provide.