HDR photography allows capturing an extended range of luminosities by combining several images taken at different exposures (a BRACKET). This is particularly beneficial for scenes that have very dark and very bright areas. Architects can use this technique to highlight the details of structures in varying lighting conditions.


How do I capture a BRACKET?


The following video depicts in clear detail the capture process. We encourage you to watch it befor reading the following guide and starting to capture



Equipment Selection:
  • Camera: Choose a camera that supports manual mode OR that has an auto-bracketing feature. Android users can capture using the ProCamX app.
  • Tripod: Use a tripod to prevent any movement between shots.
  • Scene Preparation: Find a good viewpoint for your building or structure. Make sure to avoid direct light sources, such as the sun facing the lens.

Camera Settings:
  • Manual mode: Turn on manual mode to have complete control over the capture parameters.
  • Auto-bracketing: If your camera has an auto-bracketing feature, you can use it instead. This will allow you to automatically take 3 or more photos with different shutter speeds with a single button press.

Note the following settings and make sure they are constant through the whole capture process of your BRACKET. If they aren’t, you will not be able to upload the pictures to the platform:

  • Aperture (F-number)
  • ISO
  • White balance

Shooting:

Once you have your camera set up and are ready to shoot, you'll focus primarily on changing the shutter speed for each shot in your BRACKET series. This is because the shutter speed will determine how much light is captured by the camera sensor, and this will, in turn, allow you to capture a range of exposures from underexposed (dark) to overexposed (bright).

How do I know which shutter speed to select and how many pictures to capture ?

The goal behind taking a multi-exposed BRACKET is to be able the full dynamic range of the scene, starting from the lowest brightness value (such as a dark wall corner) to the brightest value (such as light coming from a window in full sun). Here we provide a good rule of thumb to know what shutter speed you need to set up and how much pictures you need to capture :

Here’s a panorama that was captured as an example :

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First rule : There should be no white pixel in your darkest picture :

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Second rule : There should be no black pixel in your brightest picture :

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Third rule : Double the value of the shutter speed at each picture:

Example: if your first shutter speed value is 1/200, double the value for the next picture, so 1/100, and subsequently for the next pictures so: 1/50, 1/25, 1/12.5, etc… The values don’t have to be exact, it’s a general rule of thumb to double the values at each image.


Using the platform :

Here we provide a test BRACKET so the user can experiment on the platform :

Download the test bracket