Steps For Taking an Incident Light Reading

written and designed for the web by Joel Schlemowitz

[Joel Schlemowitz Film Production Pages]

[The Bolex] [The Sekonic Light Meter]

1. Set the light meter to the Exposure Index (EI) of the film you are using. [a] You will find this on the box the film comes in, abbreviated E.I.Exposure Index (EI) is also known as A.S.A. or I.S.O. All three are really the same. Note that there is a different Exposure Index for indoors (with the light bulb symbol) and for outdoors (with the sun symbol). For color film a daylight or tungesten conversion filter might also have to be used.

2. Hold the light meter directly in front of the subject with the sphere [b] pointed at the camera.

3. Depress the center button [c]

4. The needle [d] will be released and move to a reading on the foot candle scale [e]. (Note that there are f-stops marked in red on this scale too. Do not use these to set your lens, as they have no correlation to the film speed.) If you a re out-of-doors on a bright day the needle will likely pin at the top of the scale. You will have to use the HIGH Slide to take your reading. The HIGH Slide will lower the amount of light by 5 stops. The HIGH Slide is located in a metal pocket on the back of the meter. To use it, put it in the slot on top of the meter so it is behind the sphere.

5. You now turn the dial of the light meter so that the pointer [f] lines up with the number on the foot candle scale above. If the reading is between numbers on the foot candle scale [e], try to be accurate as far as the percentage above or below the number.

Be careful that you don't change the Exposure Index [a] when you turn the dial.

Importantly, if you are using the HIGH Slide then line up the number to the red pointer marked with an "H" [g] which stands for HIGH Slide.

6. Now look at the bottom of the dial. Here you will find the 1/sec scale [h] and the f-stop scale [i]. There is a red line indicating 1/50th of a second. Because the Reflex Bolex viewfinding system takes away some light, it is best to open and extra 2/3rds of a stop from the reading at 1/50th. This can also be done by reading for 1/80th of a second (there is no 1/80th on the 1/sec. scale, you'll just have to estimate).

7. The f-stop reading [i] directly across from 1/80th of a second [h], or 1/50th opened 2/3rds of a stop, is what you use to set the f-stop on the camera lens. While the meter does not include a shutter speed of 1/80 of a second on the dial you can use the "0" in 1/60th for making the reading at 1/80th of a second. If the reading is between stops, try to be accurate as far as the percentage above or below the stop.

You are now ready to shoot.

Note: If you are filming fast or slow motion your shutter speed will be effected. You can use the cine scale [j] to take your reading. Be sure you remember to also compensate for the Bolex viewfinder (see step 6).

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The material on these pages may be printed out for personal use only. Use as course handouts only with proper acknowledgment of authorship and the New School's Film Production Department.