Meyer-Optik Gorlitz Oreston 50mm f1.8 vs Pentacon 50mm f1.8

Other than the very long name of the Meyer-Optik, these two lenses are indistinguishable from each other, if the name ring is removed. By all accounts, these two lenses are identical.  When Meyer-Optik was merged with Pentacon, all its lenses were renamed Pentacon. At least initially, the zebra versions of the Pentacon lenses are probably the same lenses as the Meyer-Optik lenses. I am speculating here, but I think it's pretty close to the truth. That said, I wanted to see if there are any differences optically, between these two lenses. Keep in mind that when comparing decade old lenses, there are just too many parameters that can affect the optics. How heavily each lens was used, any abuses from previous owners, initial manufacturing tolerances (remember these are East German lenses), copy variance, etc. So, you have been warned. Take this comparison with a handful of salt.

In use, both lenses behave very similarly, even the colours are the same. The Meyer-Optik Oreston 50mm f1.8 clearly has a de-centering problem, if you look at the 100% crops. The right side is blurrier than the left side. The Pentacon is much better, showing both sides identically sharp/blurry. In terms of sharpness, both are very sharp even at f1.8 at the center, but the edges are just not very good, even at f8, on full frame. The bokeh is not so bad though.

From what I can tell, these two lenses are optically identical. Both focuses down to 0.33m, which is very good, as most 50mm lenses can only focus down to 0.45 or 0.5 meters. I do have a few MC version of the Pentacon, and I wonder if they behave the same as the Meyer-Optiks. Might be a comparison for another day.

As you can see, these lenses are no match even for today's cheap auto focus lenses in terms of sharpness and edge performance. They were cheap consumer lenses when new. For day to day use, you probably won't notice any bad corners unless you shoot flat surfaces all the time. I used the Pentacon version quite a bit before, and I enjoyed using it. The pictures it produced were good and pleasing to look at.

Identical twins separated at birth? Click for larger.

From the side. Look identical. Click for larger.

Bokeh - Canon 5D Mark II & Meyer-Optiks Oreston 50mm f1.8 @ f1.8. Click for larger

Bokeh - Canon 5D Mark II & Pentacon 50mm f1.8 @ f1.8. Click for larger

Bokeh - Canon 5D Mark II & Meyer-Optiks Oreston 50mm f1.8 @ f1.8. Click for larger

Bokeh - Canon 5D Mark II & Pentacon 50mm f1.8 @ f1.8. Click for larger

100% Crops at f1.8, f2.8 and f8. Click for 100%. Sorry for the bad framing