Creating images that are true to the moment and are bursting with authenticity is sometimes easier said than done. For example, in my house, when my camera comes out my boys suddenly stop making eye contact with me. They will honestly look everywhere except in my direction. My oldest son will literally turn and walk out of the room 90% of the time. But I can't blame them. I do the same thing. If I see someone about to take a photo that I will be in I do one of two things. A) Jump into oh crap mode and try to obtain the most flattering angles for myself. Forehead out, chin down, wasn't there something about pushing my tongue to the roof of my mouth, and don't forget to turn my body to the side and move my arms away from my body but too much that I look like I'm about to take flight. Whew! Sounds like I look real natural right about now huh? OR B) I try to avoid the previous scenario all together and pretend I don't see them taking the photo; look at my phone, talk to the person next to me, anything. There is something just a little unnerving about being in front of the camera. So how do we get the moment that inspired us to pick up our camera in the first place to unfold naturally in front of our camera and help our viewers feel what we felt.
I used to see the moment and I'd spring into paparazzi mode; gotta get the shot, try this angle, aching to get that one shot; 'look over here', 'hey stop for a minute so I can get a picture'. No wonder my kids try to pretend not to see me; maybe if we don't look at her she can't see us and she'll leave us play in peace. Now I work in stealth mode; quietly grabbing my camera and snapping one or two shots while they are in the moment and I'm done. Otherwise I'm waiting, and waiting some more, and even if they saw me and my camera eventually they have forgotten about me and what I might do and have gone back to what they were doing. Then I will either grab the shot while they are engaged and interacting with their activity or each other or maybe even engage me and ask me a question or show me what they've done. While they are engaged is key, you want that connection to help elevate the authenticity of the moment.
If they don't engage me, sometimes I will ask them something that I know will get a response; asking them about a toy they are playing with, maybe purposefully getting the name wrong so they laugh or intently look at it, or asking them a question about the other one or say something silly about them to get them to interact with each other naturally. What I try not to do is say 'look over here' or 'can you smile for me?'; that's a sure fire way to get deer in the headlights look or constipated cheese face.
When they outside and running around the movement is a great way to get authenticity. They are laughing, running, inspecting their environment. Same thing, I watch and wait for them to be truly engaged with each other or with something in their environment before I snap. Again, sometimes I'll engage them as I described before, but outside is a great way to engage them in a bigger way. Ask them to race towards you or around you. Or for example my son wanted to play with his big balloon outside and bounce it back and forth. With my camera in one hand I asked him are you ready and snapped his anticipation. Threw it and snapped again the action shot of him excited and jumping for it. There's lots of activities you can do with camera in hand. Play tag and snap while you run. Snap a few while you are pushing them on the swing. Spray them with the hose and capture their reaction (or give them the hose!).
The key is you want to elicit a response that is true to the moment. Draw out the emotion; what was significant about what you saw, put that in your photos. Try capturing it by being the quiet observer or by encouraging connection between you are your subject or your subject and their environment. Let go of expectations and constantly asking them to stop what they are doing for a photograph, learn to work yourself in what they are doing to capture them as they are.