This is a very handy tool, although these days I don’t believe they are absolutely necessary. The purpose for a light meter is to measure light output. The best meter to get is a combination incident and flash. The incident meter is for metering ambient or existing light that is not flash. The flash mode is for metering flash output. You will use these to determine flash ratios and how it is combined with ambient light. If you are using flash only, you will use the meter to measure the highlight side and the fill side separately. This will give you your flash ratios.The content you are trying to access is only available to members. Sorry.