In my previous post, we discussed about Aperture Priority and Shutter Priority modes. Here we will discuss about two other modes: Program Mode and Manual Exposure mode.
3. Program Mode
Program Mode ( P ) is almost like Auto mode but it will let you override some of the settings of your camera. Nikon uses sophisticated algorithm to program your camera to determine best exposure (correct aperture and shutter speed) value for photographs in different situation. When you frame your photograph and correct exposure can’t be achieved using pre-set value, Lo or Hi indicator in the viewfinder warns you about underexpose and overexpose and you can change ISO settings to change sensitivity.
Unlike Auto mode, Program mode will allow you to change settings such as Exposure Compensation, Metering, ISO, White Balance etc. If you want to change Shutter speed and aperture value, use main command dial (rear command dial) and it will give you different combination of aperture and shutter speed with same exposure level. When you do that P mode changes into P with asterisk ( P* ) into LCD screen which Nikon calls it “Flexible Program“. If you want to put in default settings of P mode, just rotate your command dial to left or right until P* changes to P.
4. Manual Exposure
If you want complete control of your camera, Manual Exposure ( M ) mode is best for you. Most experience photographer and pro uses this mode very often because they know how their camera is going to react under which shooting environment. In Manual Exposure mode, you can set shutter speed, aperture value in different combination as you like. When you are in Manual mode, rotate main command dial to change shutter speed and sub-command dial to change aperture value. In this mode, everything is manual and you can set them as per your need.
This was just short introduction about different exposure modes available with almost all DSLR camera and of course Nikon D90. As you go along with it and practice more and more, you will know which mode is best for you.
Happy Shooting!!!




Where is the sub-command dial?
Austin,
Sub-command dial is on the front part of your camera ( I assume lens is on the front part and LCD is on the back part of your camera). It is usually place right below the shutter release button.