PK 1.4/50mm made by CHINON or COSINA?

[Pancolart]

Distinctive features of PK mount COSINA (COSINON) compared to CHINON

COSINA:
Typical rebranded representative: PORST COLOR REFLEX
- convex rear element
- 8 aperture blades
- aperture blades turned upward
- mount has 4 screws
- focusing grease gets dry over time

CHINON:
Typical re-branded representative: REVUENON, AGFA COLOR
- rear element 100% flat
- 6 aperture blades
- aperture blades turned downward
- mount has 5 screws
- the smoothest focusing out there

Both lenses are similar size:

CHINON rear (flat):

COSINON rear (curving out):

Typical COSINA markings:

CHINON blades:

COSINON blades:

[fermy]

Well, I here have Auto Revuenon 50/1.4:

Flat rear element
Mount has 5 screws
However, 8 aperture blades
Different numbering style and focus ring
Different direction of focusing rotation

[Smoli4]

[fermy]

Yeah, most likely Chinon, since the rear element is flat. It's easy to change the number of blades. Btw, it looks exactly as AGFA Color in the parallel thread http://forum.mflenses.com/agfa-color-multi-coated-50mm-f-1-4-t50534.html Flat rear element, focus ring, filter size, even numbering style is the same.