Quote:
Originally Posted by irwjager
Steve, that's absolutely stunning! One of those images that make you go 'oh wow' out loud as they appear on (or should I say 'pop out of') your screen.
Creating "real" fake diffraction spikes is a bit of an art and requires the right tool. StarSpikes Pro in my - admittedly biased (because I got something better  ) - opinion isn't it.
The most obvious errors people make is 1. keeping the spikes too sharp (they need a slight blurring consistent with the rest of the image), 2. not treating every source of light (e.g. all other stars) the same and 3. choosing an incorrect compositing mode for blending in the starlight (an art in itself)
More subtle giveaways are incorrect (or non existent - rays shooting out of the stars do not a diffraction pattern make) diffraction patterns for the combination of angular size of the object, focal length, aperture and general expected obstruction profile for the type of scope that's being emulated.
I did a quick modeling of a 12" RC (guessed the focal length  : Edit: Doh! just saw F/9) and subsequent re-synthesis of the stars using the resulting point spread function (hope you don't mind Steve!).
The one error I can still see though (as in the original), is that the subtle color shift due to dispersion is wrong; it's diffracting in RGB palette but should have also been in the HST palette like the rest of the image...  |
Thanks for your comments Ivo. I rarely use Star spikes pro - I think I pressed "buy" too quickly on my computer screen <g>. Your rework is interesting but I'm wondering now whether fake spikes are really worth the trouble.
So what tool do you use?
Cheers
Steve