I just purchased a new lens, and I realize I have no real appreciative knowledge about lens filters. All I really know is that I have an inclination that it will protect the lens itself from damage. I usually shoot landscape (nature, parks), or nighttime (milkyway, stars). Is a lens filter like this one cheaping out? It seems to have positive reviews, but I thought I'd ask you all! I would like to protect the lens, but I don't want to degrade the quality of the lens. Thanks!