Well not only did I learn how to scan holograms, but I also learned how to take my scanner apart! Seems the inside glass surface had a foggy buildup in some areas, I suspect fumes/residue from the lubrication of the scanner, off gassing over the years.
Anyway, if anyone wants to follow up and see my results, I scanned:
#1 Carnage
#3 Venom
#4 Spider-Man
In the Hologram subset of the 1994 Fleer The Amazing Spider-Man set.
#1 Carnage shows good detail on his shoulders and back and you can tell his face and claws, and some red of the card carries through.
#3 Venom was tough because he has the least amount of image at the same depth level, but I got a good clear scan of his face, teeth and tongue and you can see his arms and body.
#4 Spider-Man is maybe my best scan in that it best captures the 3D look of the hologram. Good clear focus on Spidey's face and right hand, you can see his body, and you can get an impression of the buildings in the background.
Not a true card collector, but at times have collected cards in an ancillary manner to other interests.