Warning: The HDR Halo Effect
HDR photographs, especially edges in areas of high contrast, tend to have bright halos. You may have done everything correctly but they still appear in your image.
One thing you can try is to eliminate all sharpening on your raw files before you merge them to HDR and apply the sharpening afterwards. That helps if you have a problem image.
But another approach, if you still have the problem, that might not be so obvious is to use the Photoshop blend mode of “Darker Color” on a new layer.,
How this works is that you create a duplicate layer, change its blend mode to “Darker Color,” and use the eye dropper tool to select the color just adjacent to the halo that you want the halo to become. Quite often this will be the color of the sky just before the darker edge.
The image above originally suffered from this problem just below the edge of the deck ceiling. See the detail of the image below, before and after the fix was applied:
It was as simple to fix as using the eye dropper to sample the sky just below the deck ceiling, and then painting in that value with a soft brush. The beauty of this approach is that the brush only paints in areas that are brighter than the sky. And since the ceiling isn’t brighter than the sky, you don’t have to worry about the blue spilling over onto the ceiling.
The vertical columns also had some halos around them. This was a little more involved, as the value of the sky’s luminance is brighter the lower in the sky you go. The solution is to take more eyedropper samples as you go from the top of the column to the bottom. Using a large soft brush made it fairly easy and quick.