I do my scanning in Adobe for the most part.
THESE I scanned at high resolution for "detail"
(like 300 DPI at 200%, then "reduced it for file manageability.)

IBM -32 Twain
Everything else is at default settings (as far as contrast/ brightness...)
???????

YOUR SCAN ON THE LVC looks MUCH darker than mine (maybe because you compressed it?) but chip is lighter than that...