ed rader wrote in post #14903149
i'll be in DC in october (wife is doing the marathon) and i will carry 16-35L II, 24-70L, 70-200L f4 IS, 50 1.4, 1.4 TC and 15mm FE. i'll also have my tripod for night photography.
when i travel light i wear a vest and carry three lenses and one body. the unused gear stays in my room.
i buy my gear to use especially when i travel. the size and weight of all my lenses are taken into consideration when i buy them. the brick is probably the oddball because it doesn't travel well ... but it'll be history soon when the successor is available.
my tripod and ballhead (gitzo/markins) are just over three lbs. my camera and most lenses are weatherproof and can and have been used in the rain.
if you ever see me asking what lenses should i take? you'll know it's a rhetorical question used to announce a trip that i'm psyched about because i know what to take

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ed
different strokes for different folks, i suppose.
i understand what you're saying, but at the same time, DC is not one of those places where lugging around 30lbs of gear makes sense. the city is very flat, so there aren't many places to get scenic views across long distances. the monuments and buildings that are worth taking pictures of look better close up.
our family friendly fare for tourists primarily consists of the monuments, the museums, the landmark buildings, and our food. it requires quite a bit of walking if you want to cover all the sights. when i went out to the national parks out west, you can bet that i took all of my equipment with me, but DC is simply not one of those places where i think it's worth it. i've grown up around here, and i can assure you that the city is more fun when you're able to run around without sore shoulders.
lastly, the OP did mention that he would prefer to pack light. the fact that this will be a family trip with a baby probably means that he'll already be carrying quite a bit of extra clothes, diapers, etc as is. he probably won't have the chance to set up a tripod and do long exposures of the monuments and memorials at night, because this is a family vacation, not a photography-oriented trip (although i could be wrong on that assumption).
have fun with it. DC is a social city and there's a lot to do. save the pack animal mentality for your week-long hike through the mountains. =)