Just serviced and cleaned. Glass is immaculate, apeture works well and the focus is smooth as butter.
This 15mm f/3.5 came out in 1978 as an AI lens. It had an all-black barrel. Filters are now rear bayonet and the optics are 14 elements in 11 groups, also with CRC. The newer f/3.5 lens is a little longer, thinner and lighter than the older f/5.6.
The lens is free of haze, fungus, mold, scratches or cleaning marks.
However the lens does have Schneideritis, which manifested as a flaking of the flat black paint used on the internal retaining rings, whose main purpose is to reduce internal reflections in the lens. This does not affect the image or the lens.
I have a rear cap however the front cap is a cheap 3D printed cap that is cracked.