That is my understanding of it as well, if it looks darker, it has lower light transmission.

You would really need to take the scope(s) outside to look through them,for a proper test.

Some years ago, Nikon was advertising 'up to 98%' light transmission. When you read the 'fine print' they said it was Per Lens. So, with 7-8 lenses per scope, the actual light transmission would be closer to 84-86%.

I am not a fan of Nikon for 2 reasons:1) there are lots of vendors selling Refurbished Nikon scopes, so I wonder how many crap out on people;
2) Go to or and try to find a riflescope on there. You wont! I suspect Nikon doesn't want to 'offend' the camera customers by informing them Nikon also sells 'bloodsports' equipment.

If Nikon is ashamed of me, screw them.
Liberals are the most highly educated, stupid people I've ever met!