Biotar 75/1.5 aperture blade interchangable with 58/2?

[lwsy711]

The praktina lens arrived yesterday, it had more haze than I thought( the seller said a little ), anyway good news is it only on front elements and cleanable.

Here is what it looked like:











Next to do is finding adapter and aperture blades which might fit the lens.

By the way does anyone know how to open and reach the inner aperture ring on this lens? Had no experience with preset lens aperture ring before.
Thanks,
Wei
_________________
Camera: pentax k7, Olympus E-p1
MF lens:
M42: CZJ 135/3.5, 50/1.8, 35/2.4, 20/4, Super Takumar 35/3.5, Yashinon macro 60/2.8, CZ tessar 80/2.8(Exakta to M42), Vivitar 200/3.5
Pk: Cosinon 55/1,2
Exakta: CZJ biotar 75/1.5, Meyer 100/2.8, Meritar 50/2.9
Praktina: CZJ biotar 75/1.5, Primagon 35/4.5
Praktica: CZJ pancolar 80/1.8

[dzxw]