what are these strange artifacts on this photo?
how to avoid them?
photo is shot with canon 1200d 50mm f1.8 4seconds shutter
thank you
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Sign up to join this communityThis is flare. These occur because you're shooting into a light source, and the rays are reflecting off internal glass surfaces--most probably a UV filter if you have one on the lens. Note how the bright images "echo" the bright light sources in the image. Removing the filter can help.
I also note the image is overexposed. This is because auto-exposure systems use metering a specific way. They measure all the light in the scene, "average" it, and then set that average to be the middle point in the camera's dynamic range (middle gray). When you're night-shooting and the scene is mostly black, then that average value is actually darker than the "middle gray" value, and when the camera shifts the settings, you get overexposure. If you want black skies in your night shots, you'll want to learn how to override the AE system with EC (exposure compensation) in the Av/Tv/P modes or explicitly setting the aperture, shutter speed, and iso in M mode.