M: Manual Mode
Manual mode is all about control. Keep in mind, this mode was not designed for those of us who want to go on autopilot and shoot to our heart’s content. It was designed to allow the photographer to take complete control of shutter speed and aperture (Figure 4.17). The camera doesn’t do any of the work for you.

Figure 4.17. For ultimate control of shutter speed and aperture, use Manual mode.
When you have your camera set to Manual (M) mode, the camera meter will give you a reading of the scene you are photographing. It’s your job, though, to set both the f-stop (aperture) and the shutter speed to achieve a correct exposure. If you need a faster shutter speed, you will have to make the reciprocal change to your f-stop. Using any other mode, such as Shutter Priority or Aperture Priority, would mean that you just have to worry about one of these changes, but Manual mode means you have to do it all yourself. This can be a little challenging at first, but after a while you will have a complete understanding of how each change affects your exposure, which will, in turn, improve the way that you use the other modes.
When to use Manual (M) Mode
- When lighting and exposure get tricky (Figure 4.18). Shooting indoors through glass can be especially tricky. The wonderful thing about your D7100 is that it has an incredible ISO range with relatively low digital noise.
Figure 4.18. I took this image of apes at a zoo behind glass and wanted to avoid having my flash trigger because that would have left a nasty reflection. I decided to bump up my ISO and use a large aperture to get this shot.
- When your environment is fooling your light meter and you need to maintain a certain exposure setting (Figure 4.19). Beaches and snow are always a challenge for light meters. Whenever I’m shooting something in snow I find myself switching over to Manual mode.
Figure 4.19. A good rule of thumb in snow is to bump your exposure up one or two f-stops if it’s really sunny. That should get you closer to the correct exposure.
- When shooting silhouetted subjects, which requires overriding the camera’s meter readings (Figure 4.20).
Figure 4.20. The camera’s meter will do a great job most of the time, but when you want to get creative sometimes you need to use Manual mode. Using Manual mode allowed me to silhouette the buildings while maintaining the warm glow of the sun.
Setting Up and Shooting in Manual Mode
- Turn your camera on and then turn the Mode dial to align the M with the indicator line.
- Select your ISO by pressing and holding the ISO button on the back left of the camera while rotating the main Command dial with your thumb.
- The ISO will appear on the top display. Choose your desired ISO, and release the ISO button on the left to lock in the change.
- Point the camera at your subject and then activate the camera meter by depressing the shutter button halfway.
- View the exposure information in the bottom area of the viewfinder or by looking at the top display panel.
- To set your exposure using shutter speed, while the meter is activated, use your thumb to roll the main Command dial left and right to change your shutter speed value until the exposure mark is lined up with the zero mark. The exposure information is displayed in the viewfinder using a scale with marks that run from –2 to +2 stops with 0 indicating proper exposure. As the indicator moves to the left, the image is being underexposed, or gets darker. Move the indicator to the right and the image is being overexposed, or gets brighter.
- To set your exposure using the aperture, while the meter is activated, use your finger to roll the Sub-command dial left and right to see the changed exposure values. Roll the dial to the right for a smaller aperture (higher f-stop number) and to the left for a larger aperture (lower f-stop number).
- Note: You might have good reasons to want to overexpose or underexpose an image. For instance, as a black-and-white photographer, I’ll often overexpose my images by one-third of a stop to assure that my shadows have some details. This is just one of many creative reasons for adjusting your exposure differently than is suggested by the meter.