I think this is my last test on the Coastal Optical 60mm f/4 UV-VIS-IR Apo Macro lens. It’s a simple visual demonstration of light falloff. The camera is a Sony a7 modified for IR by LifePixel, using the Super Color sensor stack filter. I put an Expodisc on the lens and aimed it at a Fotodiox LED 5500K light source. I made exposures at f/4 through f/22.
Here they are:
There’s some noticeable falloff at f/4 and f/5.6, but I don’t consider any of it a problem.
[…] for UR and UV wavelengths as well as visible ones. I’ve tested it several times (here, here, and here), and found that it is pretty sharp, but not astoundingly so. The 120/4 would walk all […]