Sunday, December 13, 2009

First Week with a DSLR: Part 7

Experiment Results (Part 3)
Read about the experiment here.

I showed you these pictures yesterday and talked about how the shutter speed is changing the way the moving hook appears in each image. 

Today I want to explain another effect shutter speed has on your pictures. Consider these close-ups form the images above:

So, what's happening here? A couple of things. In the first image, the label is slightly blurry because of the aperture, just like the Christmas lights in the background - read here for more about this. In the second image, the label is sharp. In the third image, the label is blurry, but not because of the aperture. It is blurry because the shutter speed is too slow. The shutter speed is so slow that while the picture was being taken, the camera moved around enough to make everything in the image blurry.

So what do we take out of this? Well, what I said yesterday is still true. "If there is something moving in your picture, you can change the way it looks by controlling your shutter speed. If you want to "freeze" the action, use a larger number, if you want a motion blur, use a smaller number." But we need to add something. If you make the shutter speed number too small, it will cause everything in your image to be blurry.

So if there are things in your picture that weren't moving, but are blurry when they should be in focus, it is probably because your shutter speed was to slow (the number was too small.) This is why most pictures taken inside without a flash end up being blurry (unless you have huge windows or super bright lights.) So when you are making your shutter speed number smaller and smaller, be careful you don't go so far that everything in your picture gets blurry.