Ask people to take pictures for you

Example 1
You : Excuse me. Do you mind taking us pictures?
Stranger: Sure?
You : Thank you. You can just press the button here.
Example 2
You : Excuse me. Can you take pictures for us please?
Stranger: Certainly. Is everything set?
You : Please move to the left a bit. Thank you.
Example 3
You: Excuse me. Can you do me a favor?
Stranger : Sure.
You: We’d like to ask you to take a picture for us.
Stranger : ok…. All right, ready, one… two….
You : Thanks a lot
Example 4
You: Excuse me. Do you have time to take a picture for us?
Stranger : Oh. I am sorry. I really have to go.
You: It’s ok.