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i recently added an sb700 to my d3200 and am unsure how to determine proper amount of power to use in photos.
in another thread here on stack exchange, it was suggested that the ttl metering makes a distinction between two main situations 1) where the speedlight is being used as the main light source, and in which case shutter speed is irrelevant. 2) where the speedlight is being used as fill flash, and shutter speed is relevent.
i shoot in manual mode without the flash and would also like to shoot manual on the flash, so i am unsure if i should just be trying and erroring? should i meter my scene underexposed and than try to balance with the speedlight, and checking for accuracy of this with my histogram? or is there a more precise way of determining how much flash to use?