"In these older pictures as now, the brightest stars have cross-shaped rays. I don't think artists did that to a million pictures by touching up, it must be a camera artifact."
The thing about this, though, is that the mirrors on modern telescopes are supposed to be near perfect. They have to be in order to minimize distortion. If it's a camera artifact, then why don't all of the brighter areas show at least some minimal ray effects. It's either all or nothing. How can this be?
I don't see rays in areas, only individual stars. In any picture *from the same scope *, you will see the same number of rays, but the same star field photographed through a different scope might have a different number. Just because they look next to each other in a picture doesn't mean they are in the same area, they could be a hundred light years deeper in space, and probably are. Distance and brightness make a difference too, and atmospheric haze in the earthbound scopes.
"In these older pictures as now, the brightest stars have cross-shaped rays. I don't think artists did that to a million pictures by touching up, it must be a camera artifact."
The thing about this, though, is that the mirrors on modern telescopes are supposed to be near perfect. They have to be in order to minimize distortion. If it's a camera artifact, then why don't all of the brighter areas show at least some minimal ray effects. It's either all or nothing. How can this be?
Here's an article about getting the "starburst" effect with a camera deliberately which goes into the optics a little. They are diffraction lines. https://www.lightstalking.com/starburst-effect/ You notice his examples have many rays. The number of starburst rays on real stars depends on the internal structure of the telescope, can make 2,4,6,8 points. https://astronomy.stackexchange.com/questions/11156/what-causes-horizontal-and-vertical-lines-coming-out-of-pictures-of-stars https://www.thenakedscientists.com/articles/questions/why-do-stars-look-crosses-photographs
I don't see rays in areas, only individual stars. In any picture *from the same scope *, you will see the same number of rays, but the same star field photographed through a different scope might have a different number. Just because they look next to each other in a picture doesn't mean they are in the same area, they could be a hundred light years deeper in space, and probably are. Distance and brightness make a difference too, and atmospheric haze in the earthbound scopes.
Thanks for the additional research, fren!
No problem, now I know a new camera trick. :)