What size UV filter do I need to buy for my Nikkor lenses?

I'm in process of buying two lenses,
- Nikon 24-120mm f/4G ED VR AF-S NIKKOR Lens
- Nikon 50mm f/1.8G AF-S NIKKOR FX Lens

I've searched the web and almost everyone recommended to get a 77mm UV filter a general one so I can use a step-up rings when it's to be used with other lenses.

So the question is, is this a good choice to get this one (I'm going to get a B+W one), and do I need step-up rings if I bought this one in order to use them with the above mentioned lenses?

The only purpose a uv filter has is to protect the front element. So would not worry about having one

Those filters are for protection of the front element of the lens. Unless you are willing to screw off and on the filter every time you switch lenses, you would be better off with a filter for each lens.

By buying two separate filters you'd pay just a few bucks more, but it'll save you a lot of annoyance on the long run.

Buying 77mm filters is what i would do for filters that one doesn't leave on the lens all the time, such as circular polarizers or neutral density filters. But lens protection/UV filters are best left on all the time.

So, long story short, spend those $10 bucks extra to have one fitting filter for each lens, that can remain on it all the time. It's 58mm filter size for the 50mm/1.8G, and the other one can easily be found out by googling for its name and "filter size".It's most certainly also in the product description of the store where you buy it.

The wisdom for using 77mm is so that you only have to buy one size, as if you have to buy a filter in each size, it can cost a fortune. This makes sense when you are using and, CPL, Grads, etc.

However, since most people that buy UV filters for lens protection, and buy a filter for each lens, and keep that filter on the lens at all times, you would be better off buying the size you need for each lens. This will allow you to keep using the lens caps for your lenses, as well as lens hoods, etc.

I used to use UV filters for lens protection, but they became more trouble than worth. Dust can get trapped in-between the filter and lens, and for the lenses I don't use a lot, I was finding I was having to unscrew the filter and clean it prior to each use.

So I simply got rid of them.

While they do probably protect the lens better, I have camera insurance, so any damage is covered anyway. Camera insurance - actually it is a personal property insurance - that you can buy from your homeowner's insurance company - is a far better solution in my view. I pay only 1% of the purchase value for my gear per year, with no deductible - which is cheap.

I have a friend that just lost his camera, a DSLR costing $1, 500. He did not have any insurance, so he is out of luck. Insurance would have cost him $15 per year…

So, rather than spending up to $150 for a couple of B&W filters, consider insurance. Depending on the total value of your gear, that same $150 could provide 10years of coverage for the lenses and camera - for damage, loss, and other malady (basically everything but normal wear-and-tear).

Well do as you want in regard to the B+W brand. But they have been just too rich for my blood. I decorate my house walls with my 11x14's and 16x20's and don't feel my Tiffen filters have degraded the image at all.
When I buy a lens it is always with a UV filter. The skylights, I don't use. It is mainly as a protection filter. The lens comes to me in pristine condition (when new) so I don't do any further cleaning! I clean only the filter which is dirt cheap to replace in comparison to having a lens re-coated, not to mention the 6-to-8 weeks or longer waiting for the lens to come back from where ever the manufacturer would have to send it to.

It is enough bother to pull one lens off a camera and put it away with a rear cap and take another lens, remove the rear cap and place it on the camera without the EXTRA hassle of fooling with the filter also!

Buy a separate UV filter for each lens and keep it on them permanently. It will protect the lens from damage, dirt and scratches.
If you want to know the size, it will be printed on the front of the lens along with the focal length and aperture.

Does the front of the lens say "77mm"? Then buy a 77mm UV filter. The 50mm lens I have takes a 52mm filter.