Leica M6 TTL metering question

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In the manual that came with my camera there's a metering chart and it advises me on how to convert the EV and cd/m values into apertures and shutter speeds. I use 400 speed TMax and I want to create a chart for exposures based on my own experience so I can take the batteries out of my camera and not have that annoying red light shining in my eye.

 

When I follow this chart down I find that EV five is an object in candle light. But on Picker's chart it says EV 4.

 

When I see Fred Picker's exposure calculator the EV is 15 for the sunny 16 rule, The Leica manual says "4000 cd/m (EV 17 is the value for bright sunlight" which I assume is the sunny 16, but they could mean BRIGHT SUNLIGHT which would still put the Leica and Picker charts off by only one stop. Should I use the Leica manual to create a chart of exposure values or use Picker's?

 

Is my meter, shutter and aperture calibrated to read the light in this way?

 

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[giordano]

It's not that simple. EV16 is an exposure equivalent to 1/250 at f/16 (or 1/1000 at f/8 and so on). EV says nothing whatever about how much light there is until you couple it with the sensitivity of the film.

 

With an ISO400 film, the "sunny 16" rule gives you 1/400 at f/16 in bright sunlight - or about EV16.7. In really bright conditions - on a tropical beach or in snow - it's brighter than that, but if you're far from the equator and there's a bit of pollution in the air EV15 sound reasonable - especially as a little overexposure seldom does any harm with negative film.

 

As for candle-light, it depends entirely on how many candles, where they are, the colour of the walls, and so on and so on. I've just turned out all the lights apart from one candle a few inches away from a white wall. Using a sensitive incident light meter, I got the following readings:

 

• 1m away from the candle: EV1.5 (1.5sec at f/2)
  
• 30cm away: EV3.7 (1/3 at f/2)
  

So it's not surprising if various rules of thumb or charts give results that differ by a stop or two or three. They all work reasonably well in simple daylight situations, but elsewhere they don't do much more than give a starting point for experience.