Currently using the latest release (as of 6:10pm 7/23/19, Tiles 9362), I go to make a Bow Scope and the recipe consumes every nearby High Quality Lens, and insists it needs more lenses, leaving it stuck at 0% progress.
Just chiming in to say had this happen too!
Tried what I usually try when this happens in other recipes, like actually have the items on my person instead of nearby when crafting, etc, but nothing seemed to help. Just keeps eating all my lenses.
Also, of note, I put lenses behind a closed door to prevent them from presumably being ‘seen’ for crafting, and those lenses vanished too
maybe is correlated to the rock problem, every rock i pick up disappears unless i wield it, an even then, i cant use it as part of the recipe
Tip put all the requisite resources in one spot and move the eaten resource to a different location and when it asks for more just hold down the number corresponding to it. I managed to make a scope with 27 lenses after it finished eating them all.
That’s just blob psychosis at work. “More lenses means more seeing!”
I had to look this up. Sure nuff this is a thing. I have to wonder though. For a distance weapon such as a bow. Why would a scope make a difference when the best marksmen in the world could hit 300 yards off?
I mean the best recorded in modern times. 
The farthest accurate shot in archery under World Archery conditions is 283.47 m (930.04 ft), achieved by Matt Stutzman (USA) at the TPC Craig Ranch, McKinney, Texas, USA on 9 December 2015
This amounts to around 3 football fields and this dude was the recorded best. Not likely to match this unless we have CBM and mutant powers.
All the same. Thanks for teaching me something. Bow Scopes…heh, go figure.
Basically thats the reason, if you are in a cliff you can use the height and gravity to shoot even farther, and unless you have practice or good sight(or both) you are going to need a scope
Mmkk. Always figured 50 yards was good nuff. So I had no dea a scope would be a legit thing.