I am curious which aspect(s) of lens construction influences the quality of star-bursts? Is it the aperture blades? If so, is there a correlation between bokeh and star-burst quality?
I think it has to do with the precision of the star shaped points in the aperture when stopped all the way down. If it were perfectly round then you wouldn't get the points.
However, perfectly round apertures are generally associated with better bokeh so the two factors are actually working against each other. But you shoot for bokeh wide open or close to it. You shoot for startbursts all the way stopped down so it's a moot point anyway.
I find that the 16-35 II has the best starbursts out of the lenses I have used.
Star filters soften and degrade the whole image.
In addition to stopping down to f/11 or smaller, you'll want to try wide angle lenses, which yield better starbursts than longer focal lengths.
The number of blades = the number of star points. (Edit: providing the # of blades are even, odd #'s are doubled.)
The more round the aperture is, the smoother the bokeh and the OOF specular highlights will be, and star points will be less prominent.
I recently started using a rangefinder system and noticed it's a lot easier to get nice star bursts with these lenses than what I'd been seeing with my Canon glass, though not to say it doesn't happen with Canon glass. Many of the rangefinder lenses have a high number of aperture blades, like 10 or more, which may have an influence. But I've also gotten starbursts at quite wide aperture settings.
These were probably shot at around f/11, with a Zeiss ZM 50mm f/2 lens:
This is a crop of a chandelier from an otherwise unspectacular photo, but what surprised me about this one was that I got starbursts at f/2. It's the Voigtlander 35mm f/1.2 II rangefinder lens:
This lens has 12 aperture blades. The Zeiss 50mm has 10.
Here's one with the Canon 50mm f/1.2L at f/14. I suspect the starburst from the near street light isn't as nice as the other images because the light source is quite large, but the starbursts from the distant street lights look good:
Here's a comparison I shot a year or so ago, showing the difference between the 17-40mm f/4 L and 16-35mm f/2.8 L II. Both lenses shot at f/22 and zoomed all the way wide. This is a crop of roughly 1/4 of the full frame image.
Gee, I've spent all mt efforts trying to reduce the starburst effect in my lowlight shots and here are photographers trying to make them bigger. I must be on the wrong planet. My 85mm 1.8 makes good (big) ones.
