There's really no way to tell the difference between a Zeiss and a Swarovski scope without actually looking through both in the store and outside of the store at low light and near dark conditions side by side (which I have done). I am unable to tell the difference between a 44mm Zeiss and similar Swaros in near dark conditions (other than the $1K-$2K difference in price of course). What I can tell you about either scope is that they bludgeon any leupold, burris or nikon scope to a bloody pulp when it comes to optical clarity when it counts, which is why my guns now wear mostly Zeiss glass. Is it possible that Zeiss has better glass than Swarovski??? Maybe not better, but equally as good IMO for a better value certainly. I've heard that Kahles, Meopta, and a few others offer the same clarity for dollar value, but I haven't investigated them to base an opinion on it.