Quote Originally Posted by Tom1956 View Post
It's simply denatured alcohol. In other words, Everclear or 200proof vodka with poison added. This was a tactic the government used during Prohibition.
Yes, it's the additive that I think causes the problem (streaking). Otherwise it's just pure alcohol as you say but I find it being watered down these days. The Metho on my shelf (next to the 100% Isopropanol) is labelled as 95% Ethanol so presumably the rest is distilled water because it's cheaper. It's great for cleaning all kinds of stuff but I don't clean lenses with it.