Generate a Python function that calculates the brightness of a star in a given astro image using OpenCV library, output value in magnitudes, no scientific notation.
Galactic nursery with swirling clouds of interstellar gas and dust, 8K cinematic video style, medium-tone gradient filter, soft blue-green lighting, Canon EOS 5D Mark IV, 2:3 aspect ratio, pastel color palette, ethereal mood, high-res, fine details, q 0.95, t 0.70.
Majestic aurora borealis dancing above a frozen, desolate landscape, 8K cinematic video style, medium-tone gradient filter, soft, diffused green-yellow lighting, Sony A7R IV, 16:9 aspect ratio, pastel color palette, serene mood, high-res, fine details, q 0.95, t 0.70.
Galactic ring system with a massive, glowing central star, captured with Fujifilm X-T3, 100-400mm f/4.5-5.6G ED OSS, 2:3 aspect ratio, warm golden hue, low contrast, V.2.
Cosmic explosion of a supernova, captured with Hasselblad H6D-100c, 50mm f/2.8 Zeiss Planar, 4:3 aspect ratio, bold vibrant colors, high contrast, V.2.
Generate an abstract, futuristic cityscape under the glowing lights of distant stars, incorporating neon-lit skyscrapers, a stylized space station, and vibrant neon hues, with a bold, metallic color palette, set against a deep, inky black background, using a 1:1 aspect ratio.
Generate a hauntingly beautiful astrophotography piece with a slow pace, reminiscent of a cosmic lullaby, evoking feelings of serenity and wonder, in the style of Hans Christian Andersen's fairy tales.