Sorry Bonox, I know light pollution is a harsh fact of life in a big city, but I agree with John here. DSOs look plain pathetic in heavy light pollution filter or no filter.
I have to admit that nebulae look even more pathetic without a filter. I cannot make it to dark skies as often as I'd want to but my first couple of trips were enough so that I hardly ever bother observing DSOs from my backyard. I don't spend clear nights sitting in a corner either though, but observe planets and the Moon mostly, doubles sometimes. When seeing is good Jupiter can be quite a spectacle. Occasionally I do observe DSOs at home as target practice for when I'm next at a dark site. I use DGM NPB filter on nebulae.