They look ok steve
Cant believe the difference from my old 7x21 and my new 8x42.
As you know, the first number is the magnification and the second number is the diameter of the objective lens.
Other things being equal, the image you see gets brighter if you have a bigger objective lens because the light collected by the objective lens and poked in your eye is proportional to the area of the lens.
The lens is circular. The area of a circle is the old pi-R-squared thing, so the area of the objective lens (and so, other things being equal, the brightness of the image) is proportional to the square of the diameter.
So if you double the diameter of the objective lens your image is four times as bright.
It works just the opposite with magnification. If you double the magnification your image is one quarter of the brightness. Increasing the magnification from 7 to 8 times reduces brightness in a ratio of about 7x7 / 8x8 or about three-quarters as bright.
So overall, ignoring things like lens quality, coatings, prism styles (which you can't really ignore
) your 8x42 will be about three times as bright as the 7x21.