The standard VX3 1.5-5x20 is a one-inch scope. The illuminated 1.5-5 is listed on Leupold's website with a 20mm objective, but it has a 30mm tube.

Is it possible that the 1" and 30mm scopes both have a 20mm objective? In my way of thinking, it would be difficult to see how the 30mm scope could have a 20mm objective lens.

If the 30mm objective is, in fact, larger than 20mm (maybe 24mm or 25mm), would it be appreciably better in low light regardless of the illuminated reticle?