Reducing Ghost Artifacts
|Ghost Reduction off||Ghost Reduction on|
One of the major problems that can be encountered when shooting a High Dynamic Range exposure series is that objects in the scene may move between each image in a series. When objects move in a series of images and are later merged together, unwanted details can be created in the merged image. These unwanted details, called ghost artifacts, sometimes appear as transparent or partially formed objects. HDR Efex Pro 2 has some pretty special tools that help remove these artifacts.
Within the HDR Efex Pro 2 merge dialog, a powerful Ghost Reduction algorithm has been implemented to help reduce ghost artifacts. In the example below, we will take a look at how to make the skater whole again.
To turn on ghost reduction, click the check box in the Ghost Reduction section of the Merge Dialog. This will activate the Ghost Reference Image and apply the initial ghost reduction. Next, change the strength of the Ghost Reduction by selecting 100% to blend the original image with the image created in HDR Efex Pro 2. The percentage values determine the amount of blending of the different images together.
If the initial ghost reduction default settings are not desirable, try the following:
- Change the Ghost Reference Image to the exposure you would like the movement to be drawn from. (In this case, the default exposure '0' worked perfectly. In some exposure series, it is best to click on another exposure in the filmstrip at the top to get the results that you are looking for.)
- Reduce the Ghost Reduction strength if you have any unwanted image details in your image
To view the ghost reduction, zoom in by clicking the Magnifier button in the lower right hand corner of the image interface. The Loupe Tool appears to view the image and ghost reduction.
To move the Loupe Tool, simply click and drag it over the desired area.
Making minor adjustments helps to fix the major problem with a moving object in a series of images.
Image by Zach Petschek