Can someone explain to me the advantages of circular polarizers and uv filters?

Question

I am looking to get some accessories for my DSLR. Should I get a circular polarizer or a UV filter? Or both? I am going on a trip where I will be photographing wildlife, mountains, forests, and desert areas. Should I get one for each of my lenses, or swap them out depending on the lens and situation? Also, with the B+W filters, can you put the lens cap on them to protect them when not in use?

Answer 1

UV filters are completely useless, never buy one. Sales people will tell you it's to protect the lens but that's not true, a lens cap protects the lens. Use your lens cap when you are not shooting. A polarizer is a very useful filter to have, probably the single best filter you can buy. You can use it to punch up a sky, shoot into water and through glass. B+W makes great filters, in fact that is what I use. Just get one polarizer and switch it out when you change lenses. As long as you have the same front element size you won't have a problem and you can pop your lens cap right on top of the filter. If your lenses are not the same diameter then you have to use step up or step down rings. If you go that route, you will have to be careful with flare because your lens cap won't fit over an adapter. In that case I'd consider a second filter.



Let me amend that. UV filters are good if you are mounting your camera on a car or putting it in a really messy situation. I doubt you will do that.

Answer 2

UV Filters are not completely useless for as long you buy the best possible brand that you can afford. B+W is good. Buying the the cheapest filter that you can find can degrade you image quality. UV Filter like NC Filters helps prevent rust from collecting. These will also lessen the impact from accidentally banging your camera on table corners which could damage your lens' front element. Is it a necessary accessory, no. It is more of a personal preference. Not all of my lenses are with UV or NC filter, though having a filter just makes cleaning easier.



CPL's are for polarizing light to reduce light glare from shinny surfaces like glass and water. It also gives the sky a more bluish tone which reduces the brightness, specific to this application I would suggest buying the Graduated Circular Polarizer instead. Even with the filter on you can snap back the lens cap without any problem, some rarely remove the UV, I do remove them when shooting indoors.

Answer 3

UV filters -- no advantages. DSLRs are not UV sensitive like film used to be, so the filter does nothing whatsoever except to put cheap glass in front of expensive lenses and degrade your image quality. Some people claim you should keep one on at all times for "protection" -- I (and many others) find that idea ridiculous, as you'll be degrading 100% of your photos for the 0.01% chance that a UV filter might someday provide some kind of "protection."



A circular polarizer can be quite useful. It will darken skies, remove reflections from water surfaces (and other non-metallic things), and make color appear more saturated. Put it on when you want its effects, take it off when you don't (like all other filters).



If you don't yet have them, make sure you have lens hoods for your lenses, and keep them on all the time. Those *will* provide protection for your lenses, and will do so without degrading image quality at all -- in fact, they'll often improve it by keeping off-axis light out of your shots.



Peace.

Answer 4

Circular polarizing filters reduce the effect of reflective surfaces, and can increase contrast. UV filters on Digital cameras have almost zero effect as the color filter on sensor already performs the same function, they are mostly used on DSLR to protect the lens.



As for attaching your lens cap, with the correct filter in place the lens cap just clips on to the filter instead of the lens.