HDR Processing



Since I have a Nikon camera I bracketed in 1 stop increments using 5 frames. Since I really only want 3 of them, I throw away the +1 and -1 shots.

This leaves me with Normal, -2EV and +2EV (I wish Nikon would fix their software so that you could do this in camera).

When shooting HDR, it is important to use a sturdy tripod and to use Aperture Priority (Av or A). This will keep the aperture constant and only change the shutter speed during the various exposures.

The -2EV allows us to capture details in our highlights (bright areas of the image.

The +2EV allows us to capture details in the shadow regions of the image, Which is important since these areas are affected by noise more so than highlights. Digital cameras are also better at capturing highlights than shadows, so getting a correct exposure for the shadow areas is really important.

You should have the best tripod that you can afford and are willing to carry. The camera cannot move during the exposure otherwise aligning the images in software may not align exactly causing weird fringes and ghosting.

HDR Processing

Once I downloaded the various images into Lightroom, I will export them to Photomatix Pro or HDR Efex Pro 2. These software packages integrate into Lightroom or Photoshop making use a breeze. Both produce different results, but our main goal is to generate a High Dynamic Range (HDR) image.

Once you have loaded the three images into the HDR tool it will combine the images into one. From there you can play with a number of toggles and sliders to tweak the image. I personally like my HDR images to look somewhat "realistic". Others go for the "half-baked" look, which makes my eyes hurt. Everyone likes their HDR done differently so just play around with it. You can always re-process the image at a later date.

HDR image
Here is the resulting HDR image that I created from the three images above. If you look at it closely you will notice that the sky and trees look horrible. The colours look surreal. The trees look like they were lit by strobes and the sky has funny colours and tones that are unnatural.

Sometimes you can correct the sky by using an adjustment layer with levels, but I am going to show you another way that works great when you are going for that natural HDR look.


Now I load the image into Photoshop by exporting the resulting HDR image in Lightroom. I also export one of the bracketed images (the one with the best exposed sky). Once both of these files are open in Photoshop I shift drag the sky image onto the HDR image. Using the shift key will auto align the layers.

Once that is done I use the Quick Selection Tool and select the sky from the sky image. I then use refine edge option to get a nice selection around the tops of trees. You have to use a brush to paint areas where you want to refine the selection. This takes some practice, so don't get too discouraged. For this image I selected the sky and trees.

HDR + Normal sky
Now you can add a mask to the sky layer. Now the sky will look more natural as you have the sky from the normal image replacing the horrible HDR sky.

HDR + Normal sky with Levels Adjustment Layer
The image looks better but the sky is flat looking. This is easy to fix by adding a levels layer that only affects the sky of the normal image. To do this select the mask from the normal image and add a levels adjustment layer. Now adjust the settings until the sky fits the rest of the image.

Dodge/Burn Layer
The last thing I usually do is fix particular areas of the image using a technique called dodging and burning. This is a carry over from the film days. Basically you add more exposure burn to select areas of the image and less exposure to others dodge. This is a lot easier to do digitally and Photoshop has special tools to do this simply by painting.

First create a new layer and fill it with 50% gray. Now change the layer blending mode to overlay. Now use the dodge/burn tools to paint exposure onto that layer. Make sure to select a really low exposure setting like 5-10%.

If you view just the dodge/burn layer on its own it looks kind of weird. If the effects are too harsh you can adjust the layer opacity/fill to a lower setting.

Finished Image

Final Image
Below are some screen grabs of the Photoshop Layers for each step so you can see how the layers are configured.
Levels adjustment layer set to Lighten
Normal layer with layer mask that only reveals
the sky portion of the image

Dodge/Burn layer set to 70% opacity
I hope this simple tutorial helps you to create more natural looking HDR images.