Sparrow
Veteran
Spot and incident meters are usually set to give 18% grey for the indicated LV. However reflective and TTL meters tend to be set to what the manufacturer thinks is a normally lit scene, so they seldom agree.
Sparrow
Veteran
What he said, and if you label the meter at sunny/f16 just press the button and count how many stops it is to the “correct” exposure
Roger Hicks
Veteran
The original Kodak research indicated an average reflectance of 12-14%, and an average subject brightness range (IIRC) of 128:1 -- for outdoor subjects near Rochester, N.Y. Needless to say, there are wide variations even in averages: go to Greece, for example. In general, brightness ranges decline as you go north and increase as you go south.
The 18% grey card is a Munsell mid-tone, i.e. if you show someone a series of grey cards of different densities, they will choose 18% as a mid-tone. Originally the 18% had nothing whatsoever to do with exposure determination; Kodak recommended taking a reading off a Kodak-yellow paper packet (honestly!).
Even a poor exposure meter often represented an enormous improvement over many people's ability to estimate exposure. As Bill says, they all work pretty well, not least because there is quite a lot of latitude in exposure, especially with neg/pos, and there is no such thing as an objectively correct exposure. There is however such a thing as a perfect exposure, which is the one you want.
Spot meters -- used properly, to read shadows, not mid-tones -- were another big jump again. The first successful spot meter, the SEI, didn't even have a mid-tone index, because no film speed system is keyed to a mid-tone: negatives are keyed to shadows, and slides (and digital) to highlights.
Another name for the incident light system is the 'artificial highlight' system, which gives the game away. An incident reading has nothing to do with an 18% grey, EDIT: except insofar as an 18% grey is related to a bright diffuse highlight (typically 90% reflectance, i.e. 5x that of an 18% grey card): it will merely ensure that the highlights aren't blown.
Broad-area reflected light meters are based on the 12-14% assumption, but multi-sector meters may weight the exposure in one direction or another according to the different readings of the different sectors.
There's more about this on the site. Start with http://www.rogerandfrances.com/subscription/ps expo neg.html and go on from there.
Cheers,
R.
The 18% grey card is a Munsell mid-tone, i.e. if you show someone a series of grey cards of different densities, they will choose 18% as a mid-tone. Originally the 18% had nothing whatsoever to do with exposure determination; Kodak recommended taking a reading off a Kodak-yellow paper packet (honestly!).
Even a poor exposure meter often represented an enormous improvement over many people's ability to estimate exposure. As Bill says, they all work pretty well, not least because there is quite a lot of latitude in exposure, especially with neg/pos, and there is no such thing as an objectively correct exposure. There is however such a thing as a perfect exposure, which is the one you want.
Spot meters -- used properly, to read shadows, not mid-tones -- were another big jump again. The first successful spot meter, the SEI, didn't even have a mid-tone index, because no film speed system is keyed to a mid-tone: negatives are keyed to shadows, and slides (and digital) to highlights.
Another name for the incident light system is the 'artificial highlight' system, which gives the game away. An incident reading has nothing to do with an 18% grey, EDIT: except insofar as an 18% grey is related to a bright diffuse highlight (typically 90% reflectance, i.e. 5x that of an 18% grey card): it will merely ensure that the highlights aren't blown.
Broad-area reflected light meters are based on the 12-14% assumption, but multi-sector meters may weight the exposure in one direction or another according to the different readings of the different sectors.
There's more about this on the site. Start with http://www.rogerandfrances.com/subscription/ps expo neg.html and go on from there.
Cheers,
R.
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Sparrow
Veteran
Any one who has common sense will remember that the bewilderments of the eyes are of two kinds, and arise from two causes, either from coming out of the light or from going into the light, which is true of the mind's eye, quite as much as of the bodily eye; and he who remembers this when he sees any one whose vision is perplexed and weak, will not be too ready to laugh; he will first ask whether that soul of man has come out of the brighter light, and is unable to see because unaccustomed to the dark, or having turned from darkness to the day is dazzled by excess of light.
Plato
Plato
Mcary
Well-known
I use the Digiflash version and the battery seems fair. If you're worried about the battery going dead, just buy 3 or 4 at a time and stick one in your wallet and a couple in your bag. That way you'll havea spare even if you decide to leave your bag at home.
Al Kaplan
Veteran
I have two Weston Master V meters calibrated by Quality Light Metric to match one another. I use them mostly for incident light. The meter in my Bessa is pretty close, reading the palm of my hand.
http://thepriceofsilver.blogspot.com
http://thepriceofsilver.blogspot.com
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ZeissFan
Veteran
Don't overthink exposure.
If you tried to account for variances in shutter speed (marked speed vs. actual speed) and small variances in the aperture, you would never take a photo, because you would spend most of your time doing calculations.
Just be as accurate as you can be. Plus, it's b/w film -- not digital. You actually have some room for error.
If you tried to account for variances in shutter speed (marked speed vs. actual speed) and small variances in the aperture, you would never take a photo, because you would spend most of your time doing calculations.
Just be as accurate as you can be. Plus, it's b/w film -- not digital. You actually have some room for error.
Al Kaplan
Veteran
Zeiss fan is right. I've read that the allowable margin for shutter speed error is about 20% at speeds below 1/500 and 30% at at 1/500 and above, and that error can be in either direction. F/stops are just calculated on focal length and diameter of the diaphragm. They don't take into account the actual transmission through the glass.