erinjay64 wrote:
The problem would not be f/stop so much as internal reflections, and glare. There is not much you can do about reflections, except alter your position, to effect the direction of the lighting. Glare might be reduced some by using a small f/stop...16, or so. Try it, and see if it helps.
F16 is a large f-stop. Maybe you meant small aperture.
But in fact a small fstop/large aperture is best when shooting through glass...as long as you have focus on your subject and not the dirt on the glass.