With the recent addition of the handsome AF-S Nikkor 50mm f/1.4 to my bag, I noted that this new lens features an aperture with nine rounded blades, unlike its predecessor, the AF Nikkor 50mm f/1.8D, which has seven straight aperture blades. The reason this matters to me is that I like to use sunstars in some of my imagery to create the impression of brightness in light sources.
To test the sunstar capabilities of the new 50mm, I grabbed some Christmas lights from the rafters in the garage. With my camera on a tripod so everything would be the same except the lens, I shot some test images, all at f/16 at about 1 second, and made a direct comparison between the new f/1.4 and the older f/1.8.
Readers might recall the formula for sunstars: even-numbered aperture blades make sunstars points of that number, while odd-numbered aperture blades make sunstar points equal to twice the number of aperture blades…
I was quite pleased with the result. In recent years, rounded aperture blades have become increasingly common in an effort to give lenses the ability to create more pleasing out-of-focus areas, but this often sacrifices the crisp sunstar effect I love. But I found that while the effect using the 50mm f/1.4 wasn’t quite as dazzling as it was with the f/1.8, it still expressed the feeling of brightness.
While I had everything set up for sunstars, I thought I would experiment with a funny little do-it-yourself trick that can sometimes be useful: shaping your out-of-focus areas. It’s easy to do, but it’s also easy to screw up. In its simplest iteration, you cut a small shape into an opaque object and fit it to the front of your lens.
I used aluminum foil for my experiment, but it made the bokeh a bit too edgy. There are kits available, but part of the fun for me is doing it with household items. This was shot at the largest aperture setting available, in this case f/1.8…
I’ve heard about the shaping trick for years, but have still never tried it. I suppose that with a steady hand and patience, one could imagine all kinds of shapes.