10 kg per person, checked luggage. 2-3 kg per person as carry on. Hint, the heaviest clothing you are likely to need will be what you are wearing on the morning of departure. You don’t need to include this in your weight allowance.
On our photography tours we limit the number of passengers to increase the luggage allowance. You can take 20kg on a photo tour. This generally means, camera equipment including light laptop for processing. Plus around 8kg per person for clothing.