There are a few pitfalls to the technique of creating High Dynamic Range images in Photoshop. Here’s how to avoid them
Avoiding the pitfalls of creating HDR shots is mostly about learning where they arise in the first place. Using a tripod will go a long way to ensuring the quality of your final image, since even the slightest movement between frames can ruin your otherwise perfect shot. You can always use Camera Raw to compensate for mismatched colour temperatures, as well.
1. Misaligned shots
It can‘t be stressed too much just how important it is to use a tripod when you‘re shooting images for Merge To HDR. Even if your camera moves just a little between frames, your HDR image will be ruined.
The Merge To HDR plug-in has an option that will force Photoshop to align each frame, but it can‘t work miracles. If you haven‘t got a tripod, find a railing or solid support for your camera.
2. Colour Temperature mismatch
One reason to shoot your component images in RAW is that if your images have a colour temperature mismatch it can be corrected for each frame in Camera Raw.
When you first open the images in Camera Raw, click on each image and check the colour temperature readout on the right-hand side of the dialog. Now click on the next image and check its readout and, if it‘s not the same, change it via the slider.
3. Avoiding halos and surreal images
One of the most common flaws in HDR images is the appearance of bright, surreal halos around high-contrast edges, such as where buildings meet the sky. The culprit is heavy-handed use of the Radius and Threshold sliders when converting the image to 6-bits.
Keep the Threshold slider to a low value: in fact, it‘s often best to start with both sliders set high and reduce each until there‘s no sign of halos.
4. Correcting movement artefacts
If the component images feature moving objects it can produce a strange, ghostly effect. This is easily sorted with cloning, which you should do as a matter of course at the end of your HDR workflow. You can do it with the image still in 6-bit mode after conversion.
Use any of the cloning or healing tools, sampling an area near to the offending object. Badly ghosted objects are best cloned away completely.