Hi About incident metering and 18% grey. Only if you use a meter, not made for incident metering, the question about the angle, in which to point the meter, may be crutial, I think. But when using a meter with a spherical or invercone diffuser (meters made for Incident Metering usually have one) it will "catch the light" and measure the light hitting in from diffenrent directions. Your rule sounds like a fine rule of thumb, though. If I have a visible sun, I try not to point the meter directly at the sun - just at the blue sky.
When measuring off a grey card, I try to have the card tilted to point somewhere between the optical axes and the light source. I only use a grey card when it's obvious, that "18% grey" will not work - i.e. photographing white sheets of paper (drawings etc.) or very dark subjects, or group portraits in front of a very bright or dark background. Incident metering sounds complicated. But in everyday photographing it's really very simple. Much more simple, than all the sofisticated contrast, matrix, spot mumbo jumbo of modern cameras, trying to do all the thinking for you. Remember this: No camera has anyway of knowing, if you are photographing a White Door or a Black Horse! You have to know! In the same light, they both require exactly the same exposure value! Reflected metering will - in both cases - result in over- or under exposure - to make both the door and the horse - well, yes: 18% grey! Regards Jens -----Oprindelig meddelelse----- Fra: Dr E D F Williams [mailto:[EMAIL PROTECTED] Sendt: 25. marts 2003 06:55 Til: [EMAIL PROTECTED] Emne: Re: Hand Meters I have two light meters: (1) A simple Weston master that I've had for many years and still use; only for incident light with the Invercone attached. Its not suitable for _very_ low light conditions, but matches readings from the other meter I use (2) when there is a decent amount of light. (2) A Sekonic Digilite F which measures flash, incident and reflected light. I hardly ever use a hand meter for measuring reflected light, the cameras do that reasonably well. An interesting question is - where do you aim the meter to measure incident light? movie or TV cameramen will probably tell you at right angles to a line drawn between the camera and the subject on the side from which the light emanates. That's what I do - something I learned when working with a BBC TV crew just about the time colour TV was introduced in the UK. Where you measure depends on the contrast range of course. When the light is directly behind the camera, I point the meter towards the light source. Grey cards are useful inside a studio or laboratory, but are a nuisance outdoors. The cards I've used were 8 x 10 and too big to be convenient. The reverse side of a grey card is usually white and can be used, with the grey side, to make some intelligent approximations of something or other (contrast range?) ... I've forgotten the details, but someone else will know. I recommend the Sekonic. The meter uses one AA battery that lasts for ages. Its a reliable meter and I've used mine for about 12 years. I can't remember what it cost - about 200 Euros maybe? By the way, this one can be fitted with a spot-meter attachment. Don _______________ Dr E D F Williams http://personal.inet.fi/cool/don.williams Author's Web Site and Photo Gallery Updated: March 30, 2002 ----- Original Message ----- From: "Paul Stenquist" <[EMAIL PROTECTED]> To: <[EMAIL PROTECTED]> Sent: Monday, March 24, 2003 10:03 PM Subject: Re: Hand Meters > Because the amount of reflected light is dependent on the reflectivity > of the subject. If you're shooting a white subject, such as a snowdrift, > the reflective meter will want to render it as 18% gray, the value to > which meters are generally calibrated. An incident meter will measure > only the light, and your snowdrift will be recorded as snow white. > Paul > > Steve Desjardins wrote: > > > > OK, I'll ask the obvious question and "expose" my true ignorance. Why > > is the incident light a "better" reading? After all, it's reflected > > light that going to hit the film, no matter what is hitting the subject. > > It's also the reflected light that hits my eye. > > > > Always wanted to ask this question . . . > > > > Steven Desjardins > > Department of Chemistry > > Washington and Lee University > > Lexington, VA 24450 > > (540) 458-8873 > > FAX: (540) 458-8878 > > [EMAIL PROTECTED] >
