I am a big fan of night photography. See e.g. here: http://www.trekearth.com/members/mkamionka/photos/ I think I learned to produce pretty good pictures having simple camera (EOS300, EOS350d). my trouble began when I decided to upgrade. I bought EOS450d and then 17-85mm lens. The tripod which I used was always the lightest cheapest smallest tripod which worked out perfectly and was great for travel. I think the new lens is pretty heavy and destabilizing the whole camera. I performed some tests with same camera using this new lens and some old simple lenses. The shots with old simple lens (EF 80-200mm II) are ALL very sharp. The shots with the new heavy lens (EF-S 17-85mm IS USM) are in most cases not sharp. I took about ten consecutive shots and out of ten 1 or 2 are satisfactory but never as good as with the simple lens. Now the paradox is that upgrading the lens I get much better pictures in the daylight but much worse at night (which are my favorites). I am very curious if anybody had a similar case. Is everybody using heavy tripods? What are your favorites? Are there some heavy tripods which are not necessary very expensive? Alternatively I think about taking for the night photos the lighter simpler lenses but for the travel I would need to take two versions of each lens. I would appreciate your advice.