Hello...first post...be gentle...about time I joined a photography forum instead of just reading them. Hope this thread fits ok here.... Prompting this post was the purchase of a Praktica MTL3 on eBay. It was described as near mint, and probably seeing little use with clear glass etc etc. I'm a bit sentimental about the old Praktica cameras, since an MTL3 was the first SLR I abused when I was young. When I received this one, I found hazing and separation on the lens, and a blurry viewfinder on the body. Forget about using the aperture at all, as it feels like somebody has poured honey into the lens body, and the focus ring is little better. Film advance operated three or four times (shutter did sound good) before jamming. I think the marketing was a touch optimistic. Anyhow, not much money blown and it looks like the seller will agree to a part refund. I'll just use it for parts/education such that I am able. But on to the topic of my post...I took a photo through the viewfinder to show the seller how affected it was. I managed to focus on the muck obscuring the top part of the image, and it revealed a rainbow kaleidoscope of dribbles and swirls. Does anybody have a better idea than me of what this is? My first impression was that it is some sort of oil or other fluid. Fungus did come to mind, but it just doesn't appear as I expected (with my naked eye...fungus looks a little more 'jaggy' and tree-like). Otherwise, maybe some sort of delamitation of materials? Just curiosity more than anything else. I'm not about to try to crack into the prism/viewfinder on this camera - I hear that it's...challenging. Cheers! Damien PS...file title may mislead...it's a shot through the viewfinder with no lens on the body, not a shot of the lens.