I've been trying to find more on the cats eye effect but not having much success.
I'm sure I read somewhere that it's due to the position of the aperture, more or less recessed, but I can't find that today. I know it's caused by the shape of the aperture when seen at an angle but I can't find an explanation as to why some lenses display this more than others at the same focal length and aperture, assuming that's true.
I assume that it is possible to decrease this effect by design as it's clearly possible to increase it as with the Petzval lenses which AFAIK make this a feature. Perhaps as some Sony lenses seem to be designed to be smaller the issue is more likely? I suppose if the lens is bigger that could help? Perhaps a larger lens perhaps with a larger image circle and with an aperture which looks more rounded even when viewed at an angle would show this less?
If anyone has a source for this pls post