how to use a light meter

Joined: 11 May 2004 Posts: 3 Location: Florida

hi everyone I'm new to the forum. I have a minolta light meter and I understand about f stops and shutter speads, I'm just confused about when I leave the white ball attached and when I take it off to make my reading.
Thanks.

Joined: 01 Sep 2003 Posts: 323

I'm not sure about the Minolta, because I use a Sekonic.

Generally, the white ball is used to take 'incident' readings, i.e., the light that is falling upon the subject.

You remove the ball and turn the meeter around to measure the light reflected from the subject, which is what the meter inside the camera does.

Joined: 01 Nov 2003 Posts: 2751 Location: Luxembourg

What Orrin said...
it is basically the same for all light meters

Joined: 11 May 2004 Posts: 3 Location: Florida

Thanks
8)

Posted: Mon May 24, 2004 8:22 am

To use an incident meter (with the ball) hold the meter in the same light as the subject. You can read the highlight area and the shadow area. If the highlight and the shadow are within the range of the film you are shooting (about 4-5 f-stops) then you can use the middle of the range for your exposure. If it exceeds the range of your film, you will have to decide which is more important to you--the highlight area or the shadow area. If you take the middle of the range, the white areas will record as white and the black areas will record as black. Additionally, you will have to make some mental adjustments for certain surfaces that absorb a lot of light--animal fur, for instance, will often record as underexposed unless you make a 1 or 2 stop adjustment. Incident meters are the meters of choice for cinematographers who must control the range of light to keep within the film range. If you want to get a quick average of the scene, hold the meter with the ball facing towards the camera. This will average what the camera sees. Otherwise, aim the ball towards the light source (for highlights) and away from the light source for shadow detail.

To use a reflected meter, you aim the meter at the subject (instead of aiming the ball at the light source). No matter what color the subject, the reflected meter will assume it is an 18% gray card and give you an exposure that will record the subject as gray(or the equivalent shade of the color you are shooting). If you are aiming at a white sheet of paper and you use the indicated reading you should end up with a print equal to 18% gray. If you shoot at a black sheet of paper and use the indicated reading you should end up with a print is also equal to 18% gray.

Whichever metering system you use, you will have to stop and think with each shot--a good thing to do. You will have to choose between an array of f-stop/shutter speed combinations--all of which will give identical exposure but will yield different results.

Joined: 25 May 2004 Posts: 163 Location: Ontario, Canada

Keeping the white dome on the meter and taking incidental readings at your subject is the most accurate way to meter exposure.

Reflective metering is trying to turn the world grey. This is fine for your average scene but if you're looking at something dark (like leather) your camera will over expose, if you're looking at something bright (like snow) your camera will under expose.

The dome essentially reduces the amount of light reaching the sensor to just the right shade of grey (18%) so you will get the most accurate readings that way. If you can't get right next to your subject, look for the place that has the most similar lighting nearby and meter that with the dome on to get your best readings (i.e. if you're outside in the sun but your subject is in the shade then shade the dome with your hand when you take your reading).