When observing faint, extended objects like nebulae or galaxies through a telescope, how does light pollution complicate resolution?

It reduces the contrast between the object and the surrounding sky, making them harder to resolve

Light pollution significantly degrades astronomical viewing, not just for point sources like stars, but especially for faint, extended deep-space objects such as galaxies and nebulae. While a telescope gathers more light, it also gathers substantially more background light originating from terrestrial artificial sources. This raises the overall sky brightness surrounding the target. Since visibility depends on the contrast ratio, increasing the background noise relative to the faint light from the nebula or galaxy makes it exceedingly difficult, or impossible, for the observer's eye to separate the structure of the object from the illuminated sky surrounding it.