f/9 1/5 sec.
Deliberately moving your camera during an exposure can result in some stunning abstract photographs. I love this technique, it's a wonderful way to see your subject differently! It does take some practice and is often hit or miss, each photograph will yield such different results. It’s well worth the effort to shoot lots and lots of these. You may need to use your polarizing filter or neutral density filter to get the necessary slow shutter speeds for these images if you are shooting on a bright day.
f/25 .5 sec
f/14 .4 sec
f/4.5 .3 sec
f/32 .4 sec
Find a subject with lots of interest, containing pattern, line, color, shape, or contrast. Set an exposure that allows you to use a long shutter speed, I usually start with 1/30 second or slower. At the moment you press the shutter, move the camera in a straight line, up or down. Too little movement will just resemble a blurry photo and too much movement will result in loss of all detail. Experiment with movement speed and shutter speed until you find a combination that works for you.
Photographers often use this technique to photograph trees, their long lines do make them excellent subject matter for the technique. But think beyond trees... you can pan buildings and other landscapes, and also smaller scenes, just look for a frame filled with line and color. This can be a great thing to try on a very windy day when you are just not going to get subject sharpness, or with a subject that isn't in prime condition, blur is very forgiving! It's also a great way to create photos when you just aren't feeling very creative. Panning will get you out of that slump!
Irises f/9 1/6 sec
Lupine F/32 1/8 sec
Tulips f/18 1/30 sec
iPhone shooters can pan too, my favorite App for this is called Slow Shutter, here are some images I made in Charleston while panning with my phone: