Why am I getting a slow shutter speed with Child mode on Nikon D3100

Question

I am just starting out with my Nikon D3100 and taking pictures of my kids who never seem to sit still. I thought that Child mode would be the most appropriate mode to do this with but I seem to be getting slower shutter speeds than I would have expected and consequently the pictures come out blurry when inside with available light. The settings I have are:

• Child Mode
• Flash disabled - because I only have the built in flash and it seems to really blow out the kids faces when it's on.
• Aperture automatically set to largest value (in this case, f2.8)
• ISO automatically set to 400.
• Shutter speed automatically set to 1/20.

My thought was in Child mode I would have expected there to be a lower bound on shutter speed, say 1/50 or so, and let the camera bump up the auto ISO to 1600. Then, if the camera hit the ISO limit, it could start backing down the shutter speed to get the correct exposure, but that doesn't seem to be what is happening to me.

Answer

The manual describes child mode like this:

Use for snapshots of children. Clothing and background details are vividly rendered, while skin tones remain soft and natural.

So, while it probably affects the exposure program as well, from Nikon's own words the main concern seems to be with color rendering. Whatever effect this might have have on the automatically-selected shutter and aperture speed is "inside the black box". This is one reason I'm not fond of scene modes for learning. They're for people who want to avoid thinking about photography and just take some pictures. This doesn't really help ease you in to advanced knowledge in any way — it just gets annoying.

Since you're clearly thinking about how you want the shutter speed to be, I think it's time to abandon "child mode".

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