Zeiss Softars are special lenses with built-in mini-diffuser lenses. They are the optimum in soft focus lenses. In comparison with other diffusers, the Softars can be used at any aperture for greater depth of field without changing the softness. This is very important in portraiture. Zeiss Softars may be combined with each other and are available in two strengths: 1 and 2, with 2 having the softer effect.