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Understanding my Lightmeter...


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#1 Erdwolf_TVL

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Posted 30 November 2005 - 02:28 PM

I have recently made the plunge and invested in a all-in-one light meter. Just a couple of things I would like to confirm.

My camera's shutter angle is fixed at 155 degrees. The meter is designed for use with a 180 degree shutter.

To compensate for this, I recalibrated the meter to match the camera using the Ev adjust function.

- Is this a viable alternative to simply using a larger F-value?

(The results seem fairly consistent when compared to the camera's internal meter now.)

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Cine film invariably has both a daylight and tungsten rating.

- Should I set the light meter's ISO speed to match the lighting used?

- Or should I always leave the meter set to the larger value of the two?

- Will I get more accurate results if I held the 85 filter in front of the photo cell when measuring reflected light?

I found that the jump between tungsten and daylight ISO speeds have a very small effect on the F-Stop suggested by the meter. One stop in either direction was the biggest jump I saw in my experiments.

Any advice appreciated!

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BTW. Did search 5 pages back from present and saw no discussions to this effect.
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#2 Kevin Zanit

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Posted 30 November 2005 - 06:48 PM

-To compensate for this, I recalibrated the meter to match the camera using the Ev adjust function.

- Is this a viable alternative to simply using a larger F-value?

Your meter may have an adjustable shutter angle setting also. I know my Sekonic 508c does. But yes, the Ev adjustment will work also. It is the same as changing to a larger F stop; it is just doing the math for you.

- Should I set the light meter's ISO speed to match the lighting used?
No, color temperature will not affect the reading. The film can has two ISOs listed on it. The lower one is with a color correction filter. If you are shooting black and white film, then set the ISO according to the recommended indoor and outdoor ISOs (the outdoor one is usually higher)

-Will I get more accurate results if I held the 85 filter in front of the photo cell when measuring reflected light?
It?s not necessary if you just tell the meter (with the Ev adjustment) to compensate for the 85 (2/3 of a stop), it will be the same.


Kevin Zanit
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