How to Create an HDR Image from a Single Photo

Even the most amateur of photographers can create stunning images through the use of HDR (High dynamic range). Creating an HDR properlly requires the user to take multiple exposures of the same shot, ranging from underexposed (- stops) to overexposed (+ stops). These images are then combined by computer software to create the final image with full exposure range.

A similar result can be obtained however using only a single exposure, software is then used to pull the multiple exposures from the single exposure and create a pseudo HDR image.

What you will need:

• Camera (One capable of taking RAW photos is prefered)
• Photomatix Pro

1. The first and most important part of the process is taking the photo, the biggest problem found later on in the process is loss of image data to create the HDR from. This is where having a better camera comes in, one capable of taking RAW images means that the cameras sensor will captcher every pixel of detail and no compression will take part within the camera.

Another reason for using a better camera is the control over exposure when taking the photo. When calculating light and contrast for a photo (particularly on a bright day) a camera will increase exposure on the darker areas to make it bright enough to see the subject. This however means that detail is lost on the sky because it is now overexposed, although this is fine for a standard photo, this causes problems with HDR images as a low exposure cannot be obtained to create detail in the sky.

Below you can see an example photo taken with a cameras automatic settings, on the right we have marked where there is no longer any image data due to over exposure.

At MCWare our preference is to underexpose an image when it is taken to make sure that detail is captured in the lighter areas of the photo. Although the image is underexposed, we find there is usually no loss of data within the darker areas and so an HDR image can be created perfectly. Below you can find the same image as above taken with a lower exposure, notice the increased detail in the sky.

2. The next step is to open the image you have taken in Photomatix Pro, open the software and go to file then select open and choose the image you have taken. The file will now be converted into the HDR image.

3. You will now be presented with a 32 bit HDR image which probably won't look very nice on your system. This is because your monitor isnt capable of displaying HDR images and so we must now convert the image back to a format capable of displaying on your monitor. To do this click on the Tone Mapping button on the left side of the screen.

4. You should now see an image that looks a lot closer to the result you are after. Now you can experiment with the sliders on the left of the screen to get the result you want.

5. Once you are happy with the result click on the Process button to finalise your changes then save the image to the format of your choice.