fixed versus zoom lenses?

[beansbaxter]

If a fixed lens has the same speed as the same focal length within a zoom lens, then what are the benefits of having a fixed lens over a zoom?

[SeattleVet]

Because the fixed lens is made to be at its best at that focal length. The zoom is a bit of a compromise throughout the range. Modern zooms can be VERY good, compared to some of the junk that was available years ago, but I'll still usually go for a well-made, sharp prime lens if top quality is my object.

Having said that, I do use a couple of zooms, but, when I need the best I can produce I reach for my trusty Minolta 50mm macro.

[MotoPhotog]

Theres too many to list here.... but a few?......

Disadvantages in a zoom.... you can end up with a dirty lens faster, because when you zoom out, the lens has the slight opportunity to suck dust through the lens in dusty settings. Zooms "typically" have lower quality optics, and slower auto focusing, smaller apertures, and less friendly in low lighting/indoor situations; and some will argue that the brokeh is not as clean on a zoom lens. My biggest complaint is a lack of sharpness on the long end of a lens and more likelyness at having chromatic aberrations in photos. Not all the time, but just as a general guideline.

Advantage to me in a zoom..... besides the obvious? Saves money, more useful in most settings. I'd hate to miss a shot because I was a mere 50mm too close to a subject, for example..... Some lenses have rear focusing, so that the end of the lens is not rotating, avoiding the previous issues with some filters. Then theres the fact that we have VR and OS, and IS.... which help both. ok that was a tangent. anyway.