Your expedition bag will be transferred from camp-to-camp each day, and it should not weigh more than 30lbs. You should be prepared to carry a daypack that weighs anywhere from 8-12 pounds. Your daypack will contain drinking water (bear in mind that every litre of water weighs 2.2lbs, and you will be carrying a minimum of 3Ls/water at a time), sun protection and your lunch, along with any photography equipment you wish to carry.