I just purchased a Pentax SMC-M 40mm f/2.8 pancake lens on ebay. The lens was described as minty and in sparkling condition.
On inspection of the lens it appears that it may be less than mint condition. The second element from the front is covered in what is best described as a starfield of dust (far too many small specs to count, evenly distributed across the element). The "dust" can only be seen when illuminating the lens from behind with a torch, it is very obvious with this test and you don't have to peer into the lens to see it. Is this the first signs of the lens coating failing? I will add some photos tonight, I don't have a decent macro but it still should be able to be photographed with a nifty fity.
any thoughts would be greatly appreciated