we look at the well known beautiful little Nikon Nikkor 20mm f/4 and
the more unknown yet cult followed Tamron 20-40mm f/2.7-3.5 SP
Aspherical AF, which may be one of the ugliest lenses ever manufactured.
Shot on a tripod with manual white balance, self timer and electronic
front curtain shutter on for no vibrations. Color hue on the Tamron
shifts to green. I'm surprised that they both have an identical field
of view as zooms often fudge their numbers.