I run into this a lot, and since I haven't upgraded to CS-5 yet am stuck with manual tools to deal with it. The best method I've found so far is to insert the closest EV shot as a layer underneath the HDR layer and mask the HDR layer in the areas of the ghosting. Some tricks to help this include:
- Mask as small an area as possible.
- Open the single shot as a smart layer, which will allow you to double click it and adjust it in your RAW processor live to best match the base layer it's blending with after it's masked.
- You may even want to run that single shot in PM first to better match the processed shot. Don't worry about any part of the image which is not going to show. Try to get the parts which are going to show as close as possible.
- Depending on the shot, it may take several different EV shots, or the same shot with different processing for different areas.
Another option is to clone out the ghosting with other parts of the non ghosted subject. When faced with the type of shot you posted first, if I were going to do this I would probably select the sky surrounding the leaves using the magic wand set on pretty low, say around 5, and make sure it's on noncontinuous. Keep selecting until all the sky around the leaves is selected, but none of the leaves are. When that's done, inverse the selection so the leaves are selected and then clone from the nonghosted areas. Be sure to pick a source which has similar leaves and branches or as close to similar as you can find.
It is a bit of effort, but if the shot is worth saving each of these do work.