Trying to get a lens flare in the right position is never easy. Try this tip for more help
Usually a lens flare is applied to a black layer, with a Screen blend mode.
But, apply a lens flare directly to an image’s layer as a tester, and you can see exactly where to position it inside the filter’s menu (Filter>Render).
Then, you can re-apply this to a black layer by undoing the lens flare effect, adding a black fill layer, and then simply going to Filter menu and clicking on the option at the very top of the (Lens Flare). The previous settings are applied to the black layer.
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