With vintage/collectible lenses- much of this is from the number of lenses made. The Nikkor-SC 5cm F1.5 sells for about the same as the Nikkor-N 5cm F1.1. Less than 800 5cm F1.5 lenses made, about 5000 of the 5cm F1.1 lenses made. I found the 5cm F1.5 for "only" $1500, with a "Made in Occupied Japan" Canon III with it. Typically both it and the F1.1 go in the $3K range. The Canon 50/1.2 with the Vt Deluxe body was $400. I was not going to pay more than the 7Artisan 50/1.1, which are very good lenses (I have 2).It's always been interesting to me how stratospheric the difference in price between F1.5 and F1.1 (or more commonly F1.4 and F1.2) can be with lenses.