I have an old SMC Pentax-F 50mm F1.7 that I like to use with an adapter on my APS-C camera for portraits. It looks great, even though it has somewhat heavy CAs at f/1,7. On some backlit portraits, I get this curious artifact:
I don't want to share the entire image as I haven't cleared it with my model yet. This photo was taken at sunset, the setting sun is visible in the image, so it shines directly into the lens, producing a flare ring and this light artifact. Here's another photo at a slightly different angle:
It looks different, yet seems to be the same phenomenom.
I have never seen this type of flaring on newer lenses. The green hue seems to suggest it's some kind of combination of a flare and a Chromatic Abberation, if that makes sense? I was just wondering what causes this specific kind of flare/leak/artifact, if it has a name and in what (type of) lenses it occurs. Thank you!