High Dynamic Range (HDR)

Many of our cameras have automatic HDR modes. What is HDR and why do we need it.

HDR - The final image

HDR stands for High Dynamic Range. In photography, dynamic range is the difference between the lightest and darkest tones that can be captured in a single image. The human eye has a much wider dynamic range than most cameras, we can see details in both the shadows and highlights of a scene, even if they are very different in brightness.

HDR photography uses a technique called bracketing to capture multiple exposures of the same scene at different exposure levels. These exposures are then merged together in software to create a single image that captures the full dynamic range of the scene.

HDR photography can be used to create images that are more realistic and detailed than what is possible with a single exposure. It can also be used to create more dramatic and creative images by exaggerating the contrast between the shadows and highlights.

When we photographed the church at Holt our eyes were able to see both the detail of the stained glass windows and the surrounding stonework at the same time but our cameras struggled to do the same. The following image shows the "as metered version" of the shot above.

Canon EOS 90D

HDR the as metered shot.

As the window is a large proportion of the image, the camera's "centre weighted exposure metering" system has done quite a good job; the picture is OK but the glass is not as bright as we would like and the stone is a bit dark.

I had set up +/-manual exposure bracketing on my camera and took 3 shots, over/under exposing 1 of the shots by 1.5 stops with the 3rd as metered.

The following 2 shots are the under and over exposed versions:

HDR - the over exposed version, notice the brighter areas have burnt out; there is good detail on most of the stone (though some is also overexposed)

The underexposed version.  The brighter areas, the glass and the altarpiece have rendered clearly.  Darker areas lack detail. 

I then had to combine the 3 images in software, I used Adobe LightRoom Classic.  It is a very easy 2 click process.

I have since discovered that my camera has an automated HDR mode, as do many others.  I am looking for an opportunity to experiment with it!

Other Cameras

The Canon Powershot (Christa), Nikon CoolPix (Mike), iPhone, and the Android camera, all have a selectable auto HDR mode.  Look for the SCN (scene) control.

More Information for Phone users

How And When To Use HDR Mode On Your Android Smartphone

How To Use The HDR iPhone Feature To Shoot Perfectly Exposed Photos