Personally if your concerned about max out cabin luggage, just throw the camera bag and laptop case in a cheap backpack and you'll instantly have "less".
You shouldn't have any issues with customs, esp on the Hong Kong side. Worlds simplest border control, they really don't care about much. Canadian side coming back can be a bit more picky. but you still shouldn't have any issues. I had some issues with them coming home. At worst, just get your items documented before you leave.
Oh, once you get out the Hong Kong Airport, buy a train ticket (can't miss it) and head down town. It's pretty cheap, fun and really fast. Public transportation is some of the best in the world there, faster than any taxi you'll ever find.
And bring lots of money to spend. HK can be very cheap for photo gear, one of the cheapest places I've been. CPS has a great store in Kowloon.
I live on a bicycle, sleep in a tent, eat pasta and work in the oil and gas industry, and shoot photography because I'm bad at it.
Feedback (different website under user name sparky) http://www.mcarterbrown.com …529-sparkys-feedback.html