I don't know. . I am 60 now and my eyesight isn't what it was, but I sure don't want or need any allowances. I just need to get them closer so I am sure, or use binoculars.
I have passed numerous deer in my time because it was too dark to tell for sure just what it was in the last few minutes.
Allowances are like slippery slopes. At what point does it end.
ChuckC