Top of camera controls (right)
Although the buttons have been redesigned and are a lot easier to press the layout is identical to the D80. On the top of the camera on the right side you will find the power switch and shutter release button. Behind this are four buttons; metering mode, exposure compensation, drive mode and AF mode. The D90 now uses the standard 'press and turn the dial' method for changing drive mode, metering and AF. At the front and rear edges of this side of the camera, in line with the shutter release button are the two command dials. Press and hold the exposure compensation and AF buttons together for more than two seconds to perform a 'two-button reset', this returns all camera settings to defaults, although doesn't affect custom function settings.
Powers the camera off immediately, if there are images still buffered to be written the camera will remain on until the write has completed. When off the camera continues to display the remaining frames / frame count and card status on the top LCD panel.
Switches the camera on, this is as good as instant. There is simply no perceptible delay between turning the the dial and the first shot (you can even hold the shutter release and turn the power dial to test this).
Flick the power switch to this position to illuminate the control panels backlight's (top and rear). The backlight stays on for the 'auto meter-off' time (CSM c2 ).
Buttons (combined with dial turn)
|Metering mode (detail below)
3D Color Matrix II
• AF-A (Auto select; switches between AF-S and AF-C)
• AF-S (Single-servo AF)
• AF-C (Continuous-servo AF)
|3D Color matrix metering II
3D Color matrix metering uses a 420 pixel CCD to calculate the best exposure for the frame. 3D color matrix metering is only available with G type or D type lenses where the range information is used in conjunction with metered light.
The camera uses the entire frame for light measurement but assigns a greater weight to an area in the center of the frame (by default an 8 mm circle indicated on the viewfinder focus screen). The size of the circle used to define the "center" of the frame can be set by CSM b3 to 6, 8 or 10 mm.
The camera measures light only in a circle 3.5 mm in diameter (about 2% of the frame). This is tied to the currently selected AF area point unless dynamic AF or a non-CPU lens is used when it defaults to the center of the frame.
Top of camera controls (left)
On the top of the camera to the left of the viewfinder is the mode dial. It's very similar to the D80 (and the D70 for that matter) - though the Night Landscape creative mode has been dropped for Vari-Program: Flash Off.
Exposure Mode Dial
|AUTO|| Automatic Exposure
The D90's fully automatic exposure mode configures the camera to make most of the decisions for you, for example you can't set flash compensation, white balance, metering mode or image parameters. However you do still have control over some camera functions:
Sensitivity (Auto, L1.0 - HI 1.0)
AF Mode (AF-A, AF-S, AF-C)
Flash mode (Auto, Auto with Red-Eye reduction, Flash cancel)
Shooting mode (Single, Continuous H or L, Self-timer, Remote + Self-timer, Remote)
Image quality (all options)
|P||Programmed Auto (Flexible)
In this mode the camera automatically selects aperture and shutter speed based on the current metered exposure value, exposure compensation and selected ISO sensitivity. The Program AE on the D90 is flexible, which means that you can select one of a variety of equal exposures by turning the main command dial. Example:
1/50 F5.6 (turn left a click) P*
1/60 F5 (turn left a click) P*
1/80 F4.5 (metered) P
1/100 F4 (turn right a click) P*
1/125 F3.5 (turn right a click) P*
|S||Shutter Priority Auto
In this mode you select the shutter speed and the camera will calculate the correct aperture for the exposure (based on the reading of the current metering mode). Shutter speed is displayed on the viewfinder status bar and on the top LCD, turn the main command dial to select different shutter speeds. Available shutter speeds (1/3 EV steps):
1/4000, 1/3200, 1/2500, 1/2000, 1/1600, 1/1250, 1/1000, 1/800, 1/640, 1/500, 1/400, 1/320, 1/250, 1/200, 1/160, 1/125, 1/100, 1/80, 1/60, 1/50, 1/40, 1/30, 1/25, 1/20, 1/15, 1/13, 1/10, 1/8, 1/6, 1/5, 1/4, 0.3, 0.4, 0.5, 0.6, 0.8, 1, 1.3, 1.6, 2, 2.5, 3.2, 4, 5, 6, 8, 10, 13, 15, 20, 25, 30 sec
Aperture Priority Auto
Full Manual Exposure
|Vari-program: Flash Off
The built-in flash turns off. Use where flash photography is prohibited, to photograph infants without using the flash, or to capture natural lighting under low light. The camera selects the focus area containing the closest subject; the AF-assist illuminator will light to assist the focus operation when lighting is poor.
Use for portraits with soft, natural-looking skin tones. If the subject is far from the background or a telephoto lens is used, background details will be softened to lend the composition a sense of depth.
Use for vivid landscape shots. The built-in flash and AF-assist illuminator turn off automatically.
|Vari-program: Close up
Use for close-up shots of flowers, insects, and other small objects. The camera automatically focuses on the subject in the center focus area. Use of a tripod is recommended to prevent blur.
High shutter speeds freeze motion for dynamic sports shots in which the main subject stands out clearly. The built-in flash and AF-assist illuminator turn off automatically.
|Vari-program: Night Portrait
Use for a natural balance between the main subject and the background
in portraits taken under low light.
* Description of Digital Vari-program modes taken from the Nikon D90 user manual with permission