D. Exposure

Same reminder about the camera mode as in other chapters: Only in P, S, A, M and U1 / U2 the D7000 allows you to use all available settings.

What | Two things happen when the exposure metering is started:

• The D7000 measures the brightness in the current frame using the exposure metering method you have just set.

If you have set an exposure compensation, it contributes as a correction to the measured subject brightness.

• It translates the measured brightness into a combination of aperture, exposure time and ISO-sensitivity − the exposure control.

Where & how | The exposure metering of the D7000 always starts when you tap the shutter button = press it carefully until you feel a slight resistance.

In Nikon's default settings, the exposure metering adjusts continuously when you change the frame, point the camera to a brighter or darker subject. It is kept unchanged only when you activate the exposure lock at the same time.

Switching off the exposure meter | The exposure metering switches off after 6 s of inactivity when you don't touch the shutter release button. You can set a longer time in the custom settings menu c2 Auto meter-off delay.

What | Exposure lock means that a metered exposure is retained while you change the frame, point the camera to lighter or darker areas.

Where & How | In Nikon's presets, you have to press the AE-L/AF-L button in addition to tapping the shutter to activate the exposure lock. And keep it pressed as long as you want to keep the exposure.

The viewfinder will show AE-L, for auto exposure lock.

Note: Nikon's presets also freeze the autofocus, i.e. the focused distance is preserved as well.

AE-L/AF-L button behaviour | You can change it in the custom settings menu f5 Assign AE-L/AF-L button.

For example, you can make the button lock only the exposure without autofocus. Or if you find it inconvenient to press the shutter release and this button at the same time, you can select the menu item AE lock (hold). Then just press the AE-L/AF-L button briefly and the exposure remains locked until you press the button again. In the meantime, an AE-L indicator in the viewfinder indicates that the metered exposure is frozen.

Exposure lock with shutter release button | The D7000 can also activate the exposure lock immediately when you tap the shutter button. It then behaves like a simple point & shoot camera – metering the exposure when you tap the shutter release and holding it until you release the shutter and tap again. If you want to go for this, select On in the custom settings menu c1 Shutter release button AE-L.

Set exposure lock to other buttons | This is another option:

• to the Fn key, with the Custom settings menu f3 Fn button or
• to the preview button, with the custom settings menu f4 Assign preview button.

It is a matter of taste which you choose. These options give you the choice of using the AE-L/AF-L button for something else than exposure lock.

Where | You select the exposure metering method with the exposure metering button together with the rear control dial:

Matrix metering = brightness measurement with 2016 sensors over the entire image area and evaluation with complex logic of the camera electronics.

Centre-weighted = measurement of brightness over the entire image area with higher weighting of the centre of the image (a circle with a diameter of approx. 50% of the image height)

Spot metering = metering of brightness exclusively in a small circle around the active autofocus sensor or the centre of the image. The diameter of the spot metering area is only about one tenth of the image width, unfortunately not marked in the viewfinder.

If you want to be able to change the exposure metering method even more quickly, the preview or Fn button can be assigned to this purpose in the custom settings menu f3 or f4. There are three menu items for the different metering methods. If selected, the D7000 will use the selected metering method as long as you press your favourite button.

What | An exposure compensation makes a photo lighter or darker than the automatically measured exposure. You can apply it to any metering method as a manually selected correction.

Where | Exposure compensation can be selected by pressing the +/- key and simultaneously turning the rear control dial.

It is even faster, just by turning the front dial, if you switch on a shortcut in the custom settings menu b3 Easy exposure compensation. Select On or setting On (auto reset) there. The difference is that with the On (auto reset) an exposure compensation disappears when you switch off the camera or the exposure metering switches off after a few seconds.

In camera mode A, the front dial is reserved for aperture selection; there you have to turn the rear dial for easy exposure compensation.

What | You can select the ISO sensitivity yourself and decide whether you want to let the D7000 have a say in it too with the automatic ISO function.

Where & How | Use the ISO button and the rear dial to select a fixed ISO value.

There are two ways to make this easier – if you turn them on in the custom settings menu d3 ISO display and adjustment, not in Nikon's presets:

• The D7000 constantly displays ISO sensitivity in the viewfinder and on the top LCD, if you select there
• Show ISO sensitivity or
• Show ISO/Easy ISO.
• You can quickly change the ISO value by turning the front dial when you select Show ISO/Easy ISO.

In camera mode A, the front dial is reserved for aperture selection; there, turn the rear dial for a simplified ISO setting.

Recommendation | Select Show ISO/Easy ISO. The ISO button on the back is fiddly to find without looking. The front dial lets you change ISO sensitivity at any time without taking the camera away from your eye. And its constant display in the viewfinder and on the LCD is more helpful than the remaining frame counter you usually see there. You don't lose it, it still appears when the camera is switched off and in the shooting information on the monitor.

Auto ISO control | You can switch it on and off in the shooting menu ISO sensitivity settings. This menu also allows you to change the ISO sensitivity as you do it with the ISO button and/or the command dial.This is how the auto ISO control works:

• The D7000 uses the ISO sensitivity you set as long as the exposure time is shorter than the minimum shutter speed stored in the menu. The longest exposure time depends on the focal length when it is set to AUTO.
• If the exposure time would become longer, the D7000 automatically increases the ISO sensitivity up to the maximum sensitivity stored in the menu.
• Only when the maximum ISO sensitivity is reached does the D7000 allows longer exposure times.

The ISO automatic has three little pitfalls:

• As long as it is switched on, the D7000 will not allow a higher sensitivity than the maximum sensitivity, even if you manually set a higher one with the ISO button and see it displayed on the LCD. The D7000 will ignore your manual setting.
  
• If you are shooting with flash in low light, the auto ISO will still increase the ISO sensitivity, even though it may not be necessary due to the flash.
• The ISO sensitivity remains active when you use the manual exposure control, camera mode M. This can also be seen as an advantage − it turns the mode M, which is intended for manual exposure, into an automatic exposure control that adjusts the ISO sensitivity to a given aperture and exposure time.

The increment when changing ISO sensitivity is 1/3 light value steps in Nikon's default settings. This means that there are always two values between the whole steps 100, 200, 400 etc. − the complete series is 100, 125, 160, 200, 250, 320, 400, ....

You can change this in the custom settings menu b1 ISO sensitivity step value to 1/2 light value steps − then it is faster with only one intermediate value: 100, 140, 200, 280, 400, ...

What | For each measured image brightness plus possible exposure compensation, a number of combinations of ISO, exposure time and aperture match, resulting in the same image brightness. Exposure control means selecting one of the possible combinations.

Where & How | Exposure control depends on the camera mode.

P, AUTO, SCENE and  = programmed automatic, the D7000 suggests aperture and exposure time, in the fully automatic modes AUTO, SCENE and also the ISO sensitivity.

In mode P, you can change the aperture / exposure time combination by turning the rear dial.

This is called program shift, and the camera mode display changes from P to P*.

If the aperture and exposure time do not change when you turn the rear dial, you have probably reached the maximum or minimum possible aperture for your lens.

S = Shutter priority, you select an exposure time with the rear dial and the D7000 selects the appropriate aperture.

A = Aperture priority, you select an aperture with the front dial and the D7000 selects the appropriate exposure time.

M = Manual control, you select 

• the aperture with the front and 
• exposure time with the rear dial.

U1, U2 are identical to P in Nikon's default settings, but you can assign any other type of exposure control to them.

ISO sensitivity is fixed in all modes as you set it, or the D7000 may vary it automatically when auto ISO control Auto is on as described above.

The step size for changing aperture and exposure time in Nikon's default settings is 1/3 light value steps. You can be chang it to 1/2 light value steps in the custom settings menu b2 EV steps for exposure control. Then you lose some precision in the setting, but save a few clicks when turning the wheels.

Rear and front command dial | You can adjust their operation in the custom settings menu f6 Customize command dials, menu item Change main/sub:

• On (mode A) shifts the setting of the aperture in camera mode A from the front to the rear setting wheel.
• On swaps the assignment described above for all three camera modes S, A, M, i.e. shifts 
• the aperture selection to the rear dial and 
• exposure time to the front dial.

Short and sweet, and really very special:

Scale for exposure compensation and direction of rotation of the dials | While setting an exposure compensation, a scale appears in the viewfinder at the bottom, with the unusual order + 0 -, i.e. positive values on the left. To match this, turn the rear dial to the left for positive values and to the right for negative values.

This has been a feature of Nikon's SLR cameras since the 1960s, by then inherited from viewfinder cameras developed in the 1940s (!).

But before you shake your head at this, remember that the reading direction from left to right is only dominant in Western culture. In traditional Japanese, sometimes still today, one writes from top to bottom and the columns from right to left.

You can reverse this arrangement in the custom settings menu f9 Reverse indicators as well as f6 Customize command dials, menu item Reverse rotation.

In later models, Nikon has changed the default value but still allows you to turn the scales back again.

Changing aperture and exposure time in whole light value steps | If you want to save a few fractions of a second when setting aperture and exposure time, you can select the entry 1 step spd/aperture in the custom settings menu f3 Assign Fn button or f4 Assign preview button.

Then the aperture and exposure time jump by a whole light value with each click of a command wheel, as long as you keep the preview resp. Fn button pressed.

Centre-weighted metering | The custom settings menu b4 Center-weighted area allows you to change the size of the central metering field in this metering method (see exposure metering method).

Fine tune exposure | In the custom settings menu b5 Fine tune optimal exposure you can set a permanent correction applied to all exposure meterings. It acts like an adjustment of the camera, it is not saved as exposure compensation in the image data. Please be careful with it.