This very easy tutorial will tell you how you can add snow to your photo. I'm using a beautiful winter photo by Magda Skale.
Step 1: Open your file (file>open or ctrl+o)
Step 2: Create a new layer (layer>new>layer or shift+ctrl+N)
Step 3: Change the layer mode to screen
Step 4: Filling the layer with black by changing the foreground layer into black, and click on layer2 in your layer palette, and press Alt +Del
Step 5: Apply the graphic pen filter (filter>sketch>graphic pen), below is my setting. You can experiment with stroke pen & light/dark balance to get the best result.
Step 6: Apply the gaussian blur filter (filter>blur>gaussian blur), I put 1.5 pixel radius, but again..you can play around with it to get the best result.
Step 7: Now lower the opacity to around 70%, and you're done!
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