Which photo of the moon do you prefer?
This
Or This?
If you always use the Program Mode, the basic setting for most “Point and Shoot” or Digital Single Lens Reflex (DSLR) cameras, the first is what you will most likely get. When shooting in the program mode, the camera chooses the settings for the user. The advantage of the program mode is that the manufacturer has likely looked at the results of thousands of images taken with the camera & programed it so that under most conditions the shutter speed & aperture (lens opening) will produce decent images. The disadvantage of program mode is that there are many times a better photograph can be made by choosing the settings yourself. Because of this, many manufacturers give you a choice. If you look up “Shooting” or “Camera” mode in your manual you may find the following: (P)rogram, (S)hutter Priority, (A)perture Priority, and (M)anual. If these additional modes are available it will often be to your advantage to understand how to use each of them.
Shutter Priority (S) lets you choose how long the shutter will be open. The camera will automatically choose the lens opening (aperture) that produces the correct amount of light on the sensor for the shutter speed you chose.
Aperture Priority (A) lets you choose how open or closed the lens iris is set. The camera will automatically choose the shutter speed that produces the correct amount of light on the sensor for the aperture you chose.
Finally, the Manual (M) let you choose both shutter speed and aperture. Because the camera’s metering system is ignored in this mode it is possible for you to choose settings that will not produce an image. Some cameras will warn you that you are choosing values that are out of range for the sensor, most do not.
Use “Read the rest of this entry” for some suggestions for using your camera in the manual mode.
Why use manual? One example – ever try to take a photograph of the moon? You can change this:
to this:
by using the manual mode of your camera.
Unless you use manual settings on your camera or a lens that fills the entire viewfinder with the moon, you usually end up with a black sky & a burned out, featureless moon. The reason this happens is because the camera’s metering system averages the black sky with the bright moon. This will overexpose the image burning out the moon. Even if your camera has a spot meter function that only measures the center portion of the viewfinder, the moon is usually small enough that the camera meter includes too much black sky & ends up letting too much light on the sensor. The solution is to use the manual mode to force your camera to use a smaller f stop or higher shutter speed than the metering system would choose to reduce the amount of light falling on the sensor.
By the way, a starting point for shooting the moon is to use the “Sunny f/16” rule. The sunny f/16 rule suggests setting the camera aperture to f/16 & using the shutter speed closest to the ISO of the camera as a starting point to take pictures under bright sunlight. Since the light from the moon is reflected sunlight, the rule works well for pictures of the moon. Try taking an image using the f/16 rule, move the image to your computer and after evaluation, make adjustments for the next shot based on what you see. If you don’t have access to a computer to check the quality of the image, bracket.
Bracketing is taking images at exposures either side of what you think is correct. For example, using the f/16 rule with an ISO of 100 would suggest a shutter speed of 1/100th of a second. To bracket, take additional images at 1/50th & 1/200th of a second. If your camera doesn’t have those exact settings, use ones as close as you can get. Better yet, take 5 exposures by adding one at 1/25th & 1/400th. You are not paying for film or developing, so the more images you take the better you get to know your camera!
Some other reasons for using your camera’s manual mode include photographing subjects that don’t hang around long enough for the camera’s metering system to take an exposure measurement. Fireworks and lightning are good examples. You may need to use trial & error to set the correct shutter speed & aperture, but with practice you will get good at choosing a starting point.
Over the next couple of blog entries I’ll discuss aperture & shutter speed settings & how you can use them to improve your images.