The Petzval lens feels large in your hand, but when it was mounted to a Canon 5D Mark III the weight of the lens balanced quite nicely with the that of the camera. The Petzval has a drop-in aperture system and so each lens comes with a selection of metal plates with specifically sized circles. The larger the circle on the plate the larger your aperture opening. The Petzval comes with plates for f/2.2, f/2.8, f/4, f/5.6, f/8,f/11 and f/16 and a handful of non-circular apertures such as a star, a hexagon and a teardrop. You can also shoot without a drop in plate, which will increase the circular bokeh effect on your images—this is often how I chose to shoot with the Petzval.