How does one accurately calculate the exposure time for lightning and still keep a deep black sky?

-- Margie Kelley (rnest@pacbell.net), September 09, 1999

Answers

The effect that you are probably seeing is obtained by using a red filter. If you are using 35mm camera with 'through the lens' metering, just read the light through the filter. If you are using a hand held meter, you'll need to add 3 or 4 stops of light, depending on the density of the filter (the literature that comes with the filter will tell you). Red gives the darkest sky, orange less, and yellow less than orange.

-- chuck k (kleesattel@webtv.com), September 10, 1999.

(I don't know if chuck understands your question, it's about lightning at night I presume). I don't know whether this can be done accurately but I would use an incident light meter because a reflected lightmeter will compensate for the darkness around the lightning. Push the button of your incident meter and wait until the lightning strikes. But, as far as I can remember, you do see clouds and (green leafs) of trees during the strike of a lightning.

-- Lot (lotw@wxs.nl), September 11, 1999.

There are, I think, too many variables to assume that one answer will satisfy all situations for this question.

A suggested starting point is to use shutter speed to determine the number of lightning strikes you want exposed onto a single frame. Use aperture to control the amount of density exposed onto the film. Most lightning images you see are actually longer exposures (could be up to 10 or more seconds) with multiple lightning strikes on a single frame. Set your camera on "B" and use a black felt card in front of the lens. Try to anticipate the coming lightning strike and remove the card to capture the bolt then place the card back in front of the lens. Repeat the process for multiple strikes being very careful to not touch the camera or tripod. Advance to the next frame and bracket the aperture in one stop increments. Try different focal lengths for variety in composition as well.

The many variables regarding the sky density include- What is the ambient light in the given situation? Are you in the desert, city, suburbs?

What is the weather accompanying the storm?....clear and dry or rainy? Rainy weather will kill your hopes for a black sky.

What distance are you from the storm?

How have you composed the shot? You may want to consider what will be in the foreground either lit or sillhouted to give a sense of scale or introduce another element of drama into the image.

Also, Outdoor Photography magazine has run articles on lightning photography. You might see about their back issues.

Be safe! and good luck, Rick

-- Rick Stiles (rstiles@ghg.net), September 12, 1999.