Background first. Camera is Olympus OM40, max shutter speed (apart from bulb) 1 sec, so for longer exposures have to rely on my minolta flash IV handheld meter and a cable release. Just aquired some neutral density filters and want to take long exposure pics of the sea of between 1 & 5 minutes or so. Question now. Do hand held light meters take reciprocity failure into account over longer exposures? I will be using Ilford FP4, possibly pulled slightly, as well as my ND filters and usually for me, a red filter. Any hints & tips would be greatly appreciated.