How can I reduce blurriness when taking a photo in the dark, using only UV light?
I'm trying to take a photo of a white paper heart in UV light, to make the heart look like it's glowing. I expect that the heart is going to look, well, purple, rather than white.
I'm taking this picture against a white wall with the regular lights off, at night, so pretty much the only source of light is the UV light.
Unfortunately, it came out... rather blurry around the edges. The color is fine, the background (which is a white wall) is fine... but the edges of the heart itself are just not coming through clearly.
What can I do to have the edges of the heart show up more clearly when photographing in the dark, using only UV light?
I'm using a GoPro Hero 7 Black, set to automatic Superphoto (but I can adjust the settings).