I can't do it, but I know some that can. It needs to be so exact, so why not consider an incident light meter? Something small, mechanical and obtrusive. The best of the best is the Sekonic Studio Deluxe.
@GA2G started
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I can't do it, but I know some that can. It needs to be so exact, so why not consider an incident light meter?
Something small, mechanical and obtrusive. The best of the best is the Sekonic Studio Deluxe.