One of my favorite photographic subjects are the northern lights. It is hard to beat watching a dancing aurora display in frosty subzero temps in beautiful winter landscapes. Green, purples and even reds will show in the night sky. But in winter this does present a challenge. The snowy foreground often looks green or off color since it is reflecting the lights in the sky. Here is a quick way to fix it, no matter what white balance you were using during the shoot.
Open your RAW image in Photoshop and the Adobe Camera Raw window opens. You can see this image is a little green, the snow is picking up the green aurora color.
Choose the white balance dropper tool, and sample an area you want white in the image. The snow in the foreground works. You can see your RGB values in the histogram…they should be close to each other once you sample the snow.
Just one click and you should eliminate the green cast. Now do basic panel adjustments, making sure not to clip the highlights in the aurora. Often you will need to use Perspective control if you shot wide angle with trees close in the foreground (they won’t be vertical). Don’t forget to reduce noise…I really like Topaz DeNoise for this. That’s it, nice clean aurora shots with white snow. Let the displays begin!