If you have Trapcode’s Starglow plugin, this is the perfect time to use it. You can control the threshold of what gets affected.
If you don’t have it you can add lovely sparkle and shine in several ways.
You could do Effect>Stylize>Glow you can also choose what gets affected.
You could duplicate your layer, crush the levels to make most of it black except the lights, add a directional blur, and set the layer blending mode to screen. Then duplicate this layer and change the angle (and perhaps amount) of the blur.
You could also use a luma key of some kind to isolate the lights
To be honest screen blending mode, masks, luma keys, and any number of blurs and cor correction can achieve all kinds of different looks.
– The Great Szalam
(The ‘Great’ stands for ‘Not So Great, in fact, Extremely Humble’)
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