Ahh, I didn’t explain that well, the two layers are not independent, they are usually on one piece of glass. The stepdown ring is because they don’t make a 62mm version, so they include a stepdown ring for those who are using a 62mm lens. The UV haze filter actually has very little affect on most photos. All it really does is prevent the UV light from hitting the sensor, which will affect your colors slightly if it does.
I leave a UV filter on all of my lenses at all times. More than once, I’ve been out shooting on location and either my camera has slipped, or something has hit the front of the lens. That extra layer of glass will protect the actual lens elements from damage. On average, I break a UV filter shooting on location about once every 3 years or so, usually when I’m shooting somewhere where things might end up flying in my direction, like a sporting event or when I’m shooting climbers and little rocks get knocked off and hit the lens. So over 30 years, that would be 10 damaged lenses, since a UV filter usually runs about $10, my investment in the UV filters has definitely payed for itself a hundred times over. (Once I had an assistant trip over the corner of a tripod and knock the camera with it’s $3000 lens right onto its face. but the rock it landed on only broke the UV filter and the lens was fine.) The main time this will be a problem is when you are shooting at or around sunset, the flat glass on the front of the lens will increase lens flare under certain conditions, if you’re getting weird flares, check the UV filter first.
Most of the massive numbers of filters you needed for film are no longer necessary thanks to the ability for the camera to white balance. The ones I have listed are about the only ones you’ll really need, anything else can be done with more accuracy in post production anyway. When you’re shooting digital for black and white, don’t use the black and white adjustment in Photoshop or the converter in camera raw or Lightroom. They suck. Use the channel mixer. In addition to the presets for various color filters. Here are a couple of presets I use for shooting people. (RGB sliders with monochrome checked. I don’t adjust the constant) These are starting points, and almost always can use a little adjustment, they won’t work at all on some images.
Portraiture and most candids: 60, 90, -40
If the person is wearing yellow: 30, 90, -10
Use ad adjustment layer and then dodge and burn on the underlying layer and you’ll get great detail out of the highlights as well.