No pack will make a heavy load feel light; it might make it a bit easier on your upper body to carry, but the load on feet, ankles, and knees will be the same. What you want to do is to reduce the weight of your backpacking gear so that you can carry the heavy camera gear without too much discomfort. Reasons for backpacking lightweight are not only that it's more fun, easier, and essential for those of us with past injuries, old age or other limiting factors, but also to be able to make room fot something we just gotta have, like your photo equipment, without making the pack unduly heavy.

There are lots of articles on "lightening up" listed on the home page of this site, left-hand column.