We will use this picture that I took in the Arlington Cemetary for the tutorial.
Step 1: Go to Select>Color Range
Step 2: Make sure you have the Selection Radio button selected, select the sampled colors box, and choose highlights. Click ok
Step 3: Hit Ctrl + J (This will make a new layer by grabbing only what was selected in the previous layer)
Step 4: Hit Ctrl + J again or just duplicate the top layer.
Step 5: With the top layer selected, go to Filter>Radial Blur.
Step 6: Take the amount all the way to 100, select Zoom, and select Best quality. Now the most important part of the whole process is that you position the center of the blur at the direction of the source of light. For instance in our picture our source of light is coming from the almost the center of the left side of the image, so we will position the radial blur there. Now click ok.
Step 7: Now hit Ctrl + F (This is a shortcut that applies the last filter to the layer) 2 more time, or simply repeat the previous step 2 more times.
Step 8: With the top layer still selected, Hit Ctrl + J 2 more times, or simply duplicate the top layer 2 more times. (If the light is still not showing up well, duplicate until you get the desired amount of light)
Step 9: Merge all of the 3 zoomed layers into one. (You can do this by hitting Ctrl + E twice. Make sure you have the top layer selected, or you will merge the wrong layers.)
Step 10: With the top layer still selected (The ones we just merged), Go to Filter>Gaussian Blur.
Step 11: Select a radius of 1.5 and click ok
Step 12: You will have a bit of excessive blur so you can touch that up by using a soft edge brush, and using the edges to lightly take away the excess. Press E, or go to your tools menu and select the brush.
Step 13: Go to your brush Selection at the top, and select a 100 pixel soft edge round brush.
Step 14: Now just take the edge around the excess and gently take out the excess.
Step 15: Select the layer under the top layer.
Step 16: Hit Ctrl + L to pull up your levels or go to Image>Adjustments>Levels
Step 17: Pull the third tab to the right over to the left until you reach a bright hi-light for the image. Now click ok.
Step 18: With the middle layer still selected, go to Filter>Blur>Gaussian Blur.
Step 19: Change the radius to 2.5 and click ok.
That’s it, you are done. If you want to give it more of a real effect, I would recommend grabbing your very bottom layer (The original, or base layer), and adjusting the levels so is becomes a bit darker (Try sliding your middle slider to the right.
