grey 18%

[William W]

. . . I apologize for my English, I hope you understand.

Yes I believe that I understand what you are saying.

I think that you are saying that the light meter will make the "correct exposure" and render 18% grey the SAME in the final image whether that grey is illuminated by a strong light (EV15 / 'sunny 16') or a weaker light (EV8 - 'bright indoors') or a very weak light (EV1 'Moonlight').

WW

[Manfred M]

I read your statement the same way as Bill does; and you have identified an inherent weakness of the reflective light metering approach; everything is "normalized" based on exposing to a middle gray value, regardless of the ambient light conditions.

As per my last post, this works well for "average" scenes; but if the light level is skewed so that the scene is not "average", for instance; snow, white sandy beach, a shot with a lot of sky (for instance what happens when you take a picture of a bird or airplane in flight) or on the other side, a night shot; these images will NOT be properly exposed.

Using a spot meter with a very narrow metering angle is going to cause potentially even more issues in trying to get a correct exposure. If you spot meter an area that is in shade; shooting at that reading with brighten the scene excessively, just as metering specular highlights (an area of glare) will end up resulting in a scene that comes out too dark.

One solution that works for portraiture or product work is to use an external incident light meter as it provides exposure data based on the amount of light falling on the subject, rather than the amount of light being reflected off the subject. That takes the whole middle gray reflected average right out of the equation and gets you shots that are properly exposed.

[William W]

Of course it is entirely up to the Photographer to choose WHAT element in the photograph is to be exposed “correctly” . . . and that is not always the face or skin tones.

I think this is fairly obvious that this image was made at night-time. To expose “correctly” for those skin tones would be an entirely different image:


“Sparkler 58268v01”
EOS 5D EF135 F/2L
F/2 @ 1/125s @ ISO3200 HH

WW


***
Extract of commentary from Photographer here:

“I saw this guy playing with his kids and the sparklers and I liked the shot . . .

“So I fiddled a bit one handed and took a spot meter reading on his face – but I had to move fast because I did not want to lose the moment it was very dark not very much street light reflection or moon ambient at all - the meter reading off his skin was something like F/2 @ 1/30s @ ISO3200.

“I thought “crap” – I knew I could NOT pull 1/30s one handed with a 135mm lens, I did not even want to try 1/60s or even 1/80s – so I flicked to 1/125s braced my right elbow in to my chest waited for the moment and pulled of three shots, continuous mode - this is the middle one.”