Exposure Bracketing Calculator

Exposure Bracketing Calculator

Determine the sequence of shutter speeds needed to capture the full dynamic range for HDR.

The middle, correctly exposed (0 EV) setting.

The required difference between the darkest and brightest shot.

The difference in exposure between each shot.

Calculated Shots

How to Use Bracketing

  • **Purpose:** Use bracketing in scenes with **high dynamic range** (e.g., sunsets, dark interiors with bright windows).
  • **Process:** The camera will take a sequence of shots at the calculated shutter speeds (e.g., -3 EV, -2 EV, -1 EV, 0 EV, +1 EV, +2 EV, +3 EV).
  • **Stability:** Always use a **tripod** to ensure the frame is identical for all shots, making HDR blending easier in post-processing.

Guide to the Exposure Bracketing Calculator

The Exposure Bracketing Calculator is designed to help you capture High Dynamic Range (HDR) scenes—those environments where the shadows are very dark and the highlights (like the sky or a bright window) are extremely bright, exceeding the capacity of a single camera sensor shot.

By using bracketing, you take a sequence of photographs at different exposures, ensuring you capture detail in every tone from black to white. These images are then merged in post-processing software to create one perfectly exposed final picture.

Understanding the Inputs

To calculate your sequence of shots, you only need to define three settings based on your scene and camera:

1. Base Shutter Speed (0 EV)

  • What it is: This is your middle exposure. It should be the shutter speed that your camera's light meter determines is the 'correct' exposure for the scene (the 0 EV reading).

  • Action: Select the exact shutter speed from the dropdown that you are starting with. Note that your Aperture (f-stop) and ISO must remain constant for all bracketed shots.

2. Total Bracketing Range (± EV)

  • What it is: This defines how wide your total range of exposures will be, from the darkest shot to the brightest shot.

  • Example: If you choose ± 3 EV, the tool will generate exposures spanning from -3 EV (for capturing highlights) to +3 EV (for capturing shadows), for a total range of 6 stops.

3. Interval Step (EV)

  • What it is: This determines the exposure difference between each consecutive shot in your sequence.

  • Example: Choosing a 1 Stop interval means the camera will adjust the shutter speed by a full stop for each picture (e.g., -3 EV, then -2 EV, then -1 EV, etc.). Choosing 1/3 Stop will result in more images but finer exposure steps.

Reading the Results

The calculator generates a sequence of "result cards," each representing one photo you need to take.

  • EV Value (e.g., -3 EV, +1 EV): This tells you how much the shot is over-exposed (+) or under-exposed (-) relative to your base setting.

    • Negative EV (Blue/Darker): These are your darker shots, used primarily to capture detail in the bright highlights (like a cloudy sky or sun).

    • 0 EV (Purple/Base): This is your middle shot, representing the standard exposure.

    • Positive EV (Orange/Brighter): These are your brighter shots, used primarily to capture detail in the deep shadows and dark areas of the scene.

  • Shutter Speed: This is the precise shutter speed your camera must be set to for that specific shot (e.g., 1/125 or 1").

Practical Tip: The Tripod is Mandatory

For successful HDR blending, every image in the sequence must be perfectly aligned. You must use a sturdy tripod and ensure your camera does not move at all between shots. Use a shutter release cable or the camera's timer to prevent touching and shaking the camera during the exposure sequence.