Cosinon 50mm F1.8:

Another quality lens from a well known Japanese manufacturer. This lens is nice and sharp even wide open and no evidence of any chroma, even @ F1.8. An all metal lens built to last a lifetime. We were really very impressed with the optical qualities of this lens.

They are very rare now, and this is the only one we could source during the past 9 years of our relentless search for quality M42 lenses. 

Sample Photos:

Click on image for larger size. 

F1.8 1/200th	F2.8 1/160th	F5.6 1/80th
F8 1/40th	F1.8 1/160th on 15mm macro extension tube	F2.8 1/160th on 15mm macro extension tube
F5.6 1/100th on 15mm macro extension tube	F8 1/50th on 15mm macro extension tube