Frequently enough photos are blurry. I decided to check the settings some of these pictures and see how many of my blurry photos violate Peter Carey’s rule for sharper images which you can read about here. The image above has a focal length of 55mm and exposure time of 15 seconds. Yes, the camera was on a tripod as I was taking night photographs trying to capture the thousands of fireflies flashing about. Unfortunately this was in a city and there just was too much light for effective lightning bug pictures. According to the rule of thumb, the exposure time should have been 1/55 second or faster. if the camera was handheld. In this instance the camera was probably bumped.
Another case where the shutter speed is too slow for the focal length. This was taken at 21mm focal length and 1/2 second exposure time. It should have been at 1/21 second or faster in order to produce a sharper image. Taken again in the evening with the light going away quickly so the camera was compensating for the reduced light.
The above image was taken with a focal length of 21mm however the shutter speed was 1/30 of a second producing a sharper image. Another one of those details to improve my photographs.