Luggage and bags:
Extra bags might come in handy, if you like to buy some souvenirs, like this delicious honey!!!
Clothing/Shoes/Weather Gear: Khabarovsk is in Siberia, so it can really get cold!!! Be sure to pack warm things! I always like the 'onion principle' - layer by layer! And a nice t-shirt might help you in some of the really overly heated rooms!!!
It is NOT usual to see Russians in shorts, so I take 1 or 2 pair to wear only in the hotel or in the evening to relax. During the day Khakis or dark colored clothes is the guide. Jeans and sneakers are not usual attire either in Russia. These items are very expensive for the people and you will be noticed if you wear them.
Photo Equipment: Check with your guide or the officials, but it is common to need an official Photo certificate to take photos in official buildings or museums.