You say you've not done anything like this for years. Are you in good physical shape? Even with lightweight backpacking gear, with the camera equipment you're considering taking, you may end up with a very heavy backpack. I've been a backpacker and a photographer for most of my life. I've never taken any camera gear with me that comes close to what you're considering. But, you may be in very good shape and if so, not bothered by a heavy pack...or are only carrying the pack to a specific location, camping there for a few days and then hiking out. Also, before you go, fill your backpack with all you're considering taking and go for a 10 mile hike and see what the pack feels like. Try out your water filter, stove, sleeping gear etc...and know how to put up your tent. From your post, I'm led to believe you know little about backpacking. And, you're going alone as well. I'm not trying to discourage you at all...just pointing out the need to know your gear and that you need to be in appropriate physical condition. Perhaps you're much younger than most of us in our group. Youth can compensate for a lot.

A little over a week ago my wife dropped her backpack onto my D810. The camera functioned well enough, but in the process she broke the top LCD window. I contacted Nikon and they provided me with the place to send it to for an estimate.

In this week and a half since posting it to the service center I received the estimate, approved the service and I have the camera already back as good as new. They serviced the repair, installed firmware updates, cleaned and tested meter and sensors, and the camera looks almost like a brand new body.

I have owned Nikon since the mid 70's. I have only had a couple of occasions to use their service. One other time I sent in my D600 for them to check about the oil spotting. They confirmed it and sent me a brand new D610 which I am still using a couple of years later. I never even requested a new camera at the time.

This post isn't intended to put down other manufacturers. I am sure the others do their best as well. I am just pleased they have been very fast with their service. A week-and-a-half from my door to theirs and back.