This is my Canon 550D DSLR with the Helios 44M lens off my 1979 Zenit EM. This is my £1.99 (cost of the M42 to EF adaptor) alternative to a Petzval lens. I really like the shallow depth of field I can get. Spec: the lens has 6 elements in 4 groups, the 58mm focal length equates to 93mm on my DSLR.Taken by chrisg35mm with a Canon 550D loaded with digital film. These tags describe this photo: dslr, canon, petzval alternative, lens, 58mm, 44m, and helios. This photo can also be found in the album Helios 44M 58mm Lens.