The Pentacon 50mm f/2.4 was VEB Pentacon's entry-level standard lens for the Praktica SLR range, a lower-cost alternative to the better-known Pentacon 50mm f/1.8 auto and MC primes. It equipped budget Praktica bodies through the late 1970s and 1980s, giving buyers a cheaper way into the M42 system.
It uses a simpler, smaller optical formula than its faster f/1.8 sibling, built around a modified Tessar-type layout with automatic diaphragm coupling and a manual aperture ring stopping down to around f/16. Mounted in M42 screw thread, it shares the compact size typical of Pentacon's cheaper Dresden primes.
Stopped down to f/5.6-f/8 it is respectable for a budget design, though wide open it shows softer contrast and more field curvature than the f/1.8 Pentacon or the Zeiss Jena Pancolar it was pitched below. Bokeh from the smaller aperture and simpler formula is less smooth than faster period standards.
As the budget option in the Pentacon 50mm lineup, it sells for less than the f/1.8 version used and is often overlooked. Worth checking for haze on the rear elements, a common issue on cheaper Pentacon Tessar-type designs, and confirming the aperture pin still actuates smoothly.