I got a Nikonos III camera for a bargain, and the seller threw in an underwater lightmeter. I have never used anything like that, and would appreciate any help. In particular, do I point the light sensitive snout of this meter towards the subject, or towards the source of light? Any other tips for shooting underwater? I will not go deeper than 2 meters and won't be using flash. Here's what the meter looks like. It is marked "Farallon Oceanic".