To start, select an image that has a bright light source in the background, or at least the appearance of a backlit scene so that the direction of the shadows will make sense. On an overcast day this could simply be a cloudy sky background, or it could be the direct sun at sunset. You could even do it in the studio with a light source just out of frame. Either way, starting with an image in which it would be possible to have actual lens flare will make the end result that much more believable. That said, in the digital realm there are no rules, and sometimes when it comes to getting creative with lens flare, putting the flare in an optically “incorrect” position is no big deal at all.
Next, choose Render > Lens Flare from the Photoshop Filter menu.
In the Lens Flare window that opens you’ll see a small preview of your image, as well as a brightness slider. Drag that slider toward the right to increase the brightness considerably, just so you can see it well while you’re working with it. You can always dial it back later if you like.
Next, click anywhere on the preview image to position the “light source” from which the flare will originate. If you’re not happy with the placement, click and drag to move the source around and watch how the halation changes. I find that the best source position is in an upper corner of the frame—unless, of course, the brightest part of the background is elsewhere. But again, we’re trying to get creative here, so feel free to put that light wherever you see fit.
Next, choose from the type of lens that creates the flare. The longer the lens, the fewer of those round spots, or halations, you’ll see. Some photographers like them, others don’t. There’s no accounting for taste, though I prefer to see them a bit, otherwise flare just becomes strong backlighting that saps contrast and saturation. I tend to like the 35mm Prime lens setting because of its pronounced yet not extreme halations, but choose whichever lens produces the flare that’s most appealing to you. Click OK.
With the lens flare now in place, it’s time to give the image the warmth boost that so often accompanies lens flare, particularly when it’s caused by a beautiful sunset.
To start, I use the Photo Filter Adjustment Layer to add an orange Warming Filter, which when set to an opacity around 25, where it defaults, will produce a nice strong overall warmth across the image. If your image is already warm enough, you may find you can skip this step.
I then repeat the process of adding a warming filter via an adjustment layer, but this time I set the layer mode to Soft Light and the strength of the adjustment to 50%. This not only increases contrast, but it really adds an overall-too-strong warmth to the scene.
That’s okay, because next I like to use a gradient fill to mask part of that layer and leave the warmth only in the quadrant of the frame nearest to the light source. I can further tweak this heavy warmth with a traditional paintbrush on the mask. Sometimes leaving just a bit of the strong warmth where the light source first hits the subject makes for a little more believable flare. After all, what we want is for the image to look a bit more authentic, not less.
And with judicial use of these simple tools, manufacturing your own lens flare in Photoshop is a straightforward task that works really well to add that authenticity to practically any image you’d like.