Nikon 80mm f4 Nikkor for Nikonos brand_Calypso which displaces an indicator in

which displaces an indicator in the viewfinder

but these won't be detrimental to image quality–and you want to use this lens wide open anyways

The metal is aluminum

easy to read bubble level

Paterson 3-reel Super System 4 developing tank

Nikon 80mm f4 Nikkor for Nikonos brand_Calypso which displaces an indicator inThe Nikon 80mm f4 is designed for use in or out of the water; it's only one of two Nikonos lenses that can do this (the other is the standard 35mm f2. 5.) In excellent condition, with clean glass. Please note: this lens is for the Nikonos underwater camera system, not the much more common (and terrestrial) Nikon F mount. It will not work on an F mount camera. Do not buy this for a Nikon F mount camera because it does not fit and will not work.