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Waving Black Card Technique

(Dodging a Scene in Front of the Camera)

What's Dodging?

Back in the film era, we would block the light coming from the enlarger.

This was called dodging.

When part of the light coming from the negative was dodged, that area on the photography paper didn't get as dark.

Dodging with a Camera

Eadweard Muybridge did dodging inside his view camera.

He installed a sky shade, a board, inside his camera.

When flipped down, the board blocked (dodged) the light coming from the sky.

Muybridge would expose the entire scene for, say, one minute.

After one minute:

• The sky was exposed correctly.

• The foreground was underexposed (too light).

Muybridge would flip the sky shade down, and continue exposing the foreground until it received the proper exposure.

The properly-exposed sky would not become overexposed because the sky shade dodged the sky light from reaching the film.

If you don't have a view camera, you can dodge in front of your camera.

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Example

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No Dodging Sky Dodged

The above photographs were taken from my porch on a rainy day.

The camera was on a tripod.

The lens was focused manually by switching the lens to MF, and turning the focusing ring.

I looked through the viewfinder, while holding a black nylon bag in front of the lens.

I positioned the bag in the viewfinder where the bright sky was located.

Keeping the bag in the right position, I stood up and looked at the bag.

I noted the position of the bag relative to the landscape.

The bag was just above a lily pond.

A #10 welding filter was placed on the lens.

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The filter was used as an inexpensive ($5!) neutral density filter to reduce the amount of light reaching the sensor.

The lens opening was f/3.5.

The shutter speed was thirty seconds.

I pressed the shutter release, and gently waved the black nylon bag in front of the lens, just "above" the lily pond.

Again, the position of the bag relative to the landscape, the lily pond, corresponded to the location of the sky in the viewfinder.

I counted slowly to twenty-five, and removed the bag for the rest of the thirty seconds.

Long Exposures Needed

You need to use long exposures to minimize card-waving mistakes.

If you wave the card in the wrong spot:

• During a two-second exposure, it'll show.

• During a thirty-second exposure, the mistake won't be visible.

To enable long exposures:

• Use the lowest IS0 setting.

• Use a physically small lens opening, such as f/22.

• Photograph early or late in the day, and on overcast days.

• Use a Polarizing filter to block about one stop of light or a welding filter.

If you pursue this technique, get a very dark neutral density filter or a variable neutral density filter.

Equipment Needed

• Camera with bulb shutter speed

Set you your camera to manual exposure (M) on the exposure mode dial.

Twirl the knob to change the shutter speed to slower-and-slower shutter speeds.

The next shutter speed after thirty seconds is Bulb, if your camera has the feature.

• Tripod

• A timer or timer app for your smart phone.

A timer that beeps each second is handy.

Otherwise, you have to watch the timer while watching the card waving.

Having an assistant run the timer is even better.

Determine the Exposures

Camera Settings

Set your camera to:

• The lowest ISO setting.

• A physically small lens opening, such as f/22.

• Set the exposure mode dial to A or Av. 

• Spot metering, if your camera has this feature.

Measure the Bright & Dark Areas

Point your camera at the bright part of the scene, and press the shutter release gently to take a light reading.

Note the shutter speed suggested by your camera.

Let's say it's five seconds.

Point your camera at the dark part of the scene, and press the shutter release gently to take a light reading.

Note the shutter speed suggested by your camera.

Let's say it's twenty-five seconds.

Bright area

5 seconds

Dark area

25 seconds

So, your total exposure time will twenty-five seconds.

You'll wave the black card for twenty seconds, and then will remove the card for the last five seconds.

Take the Photograph

1) Place your camera on a tripod.

2) Set the lens to manual focus (MF).

3) Focus the lens.

4) Set the exposure mode dial to M (manual).

5) Set the shutter speed to Bulb.

Go to Bulb Shutter Speed.

6) Set the timer to twenty-five seconds.

An assistant makes the next steps easier.

7) Position the card in front of the camera where the bright area is located in the viewfinder.

8) Press the shutter release and start the timer.

9) Wave the card gently, for twenty seconds, and then remove the card for the last five seconds.

10) Press the shutter release to close the shutter.

Easier Methods

Easier may not be as much fun, though.

You can create a similar effect using a graduated neutral-density filter or software.

A graduated neutral-density filter may not work well when there's:

1) A huge difference between the bright and dark areas.

A graduated neutral-density filter can't deal with an early sunrise and a still dark foreground.

2) The bright area isn't across the entire top of the scene.

If you're photographing a sailboat, a graduated neutral-density filter will darken the sky and part of the sail.

More

Black card photography Part 1 Hanjié Wu

Flickr: Black Card Technique Group

Shutter Speeds: Long