N90s Concise Instructions

The following information is transcribed from Thom Hogan's Nikon Field Guide, no longer in print (Copyright 2000 Thom Hogan). Copies sometimes are still available used on eBay.


Variations between the N90 and N90s

Note: The N90 and N90s are known as the F90 and F90X, respectively, in markets outside the U.S. The variations listed below apply to those models as well.

The N90s differs from the original N90 in several aspects: 

  1. The N90s allows you to select shutter speeds in 1/3-stop increments in M and S modes. The N90 allows you to choose shutter speeds in whole stops only.
  2. The predictive autofocus system and motor drive on the N90s are faster, operating at up to 4.1 frames per second, as opposed to only 3 frames per second with the N90.
  3. The N90s has better gaskets and weather seals than the N90.
  4. The N90s does not allow you to set the self-timer to take two sequential pictures. The N90 does. 
  5. The N90s does not have the warning beep function of the N90, unless you use the Sharp Wizard Electronic Organizer or Nikon Photo Secretary. 
  6. The MB-10 grip’s vertical shutter release works when used with the N90s, but does not function when used with the N90 unless you have your camera modified by Nikon.
  7. The N90s uses the AC-2E card when used with a Sharp Wizard Electronic Organizer; the N90 uses the original AC-1E card. 
  8. The N90s has enough memory to keep 36 rolls of exposure information to pass to a PC or Sharp Wizard Electronic Organizer; the N90 can store a maximum of only two rolls of exposure information. 

N90s/F90X LCD Error Messages

HI — Current settings will overexpose shot.

LO — Current settings will underexpose shot.

FEE — AF lens is not set to smallest aperture in Multi-program (P) or shutter-priority (S) modes, or Speedlight is not set to TTL mode in P mode.

END and O__ symbol blink — End of roll has been reached, rewind film.

battery blinks — Batteries are low; replace them.

E —  Frame counter indicates that no film is loaded in camera.

E and O__ blink — Roll has been rewound.

F-- — Lens has no CPU to support matrix metering.

matrix blinks (in matrix mode) — Lens has no CPU to support matrix metering; camera automatically resets to center-weighted metering.

BULB blinks — Cannot set bulb shutter speed in shutter-priority (S) exposure mode.

ERR, ISO, and DX blink —  Non-DX coded film or incorrect DX code detected.

O__ blinks — Film is loaded incorrectly.

[ ] blinks — when Speedlight is used — Wide-area AF not available with flash; camera automatically defaults to spot AF.

LCD all black — Camera is too hot.

LCD slow to respond —Camera is too cold.


N90s/F90X Viewfinder Error Messages

> < symbol blinks — Autofocus is not possible.

< symbol appears — Subject is not in focus, or is located closer than lens’ minimum focusing distance.

> symbol appears — Subject not in focus, or lens not set on infinity when TC-16A is being used.

HI — Current settings will overexpose shot.

LO — Current settings will underexpose shot.

FEE — AF lens is not set to smallest aperture in Multi-program (P) or shutter-priority (S) modes, or Speedlight is not set to TTL mode in P mode.

F-- — Lens has no CPU to support matrix metering.

Green flash symbol appears — Camera recommends using flash.

Red flash symbol appears — Flash is ready.

flash symbol blinks — Flash may not have been sufficient for proper exposure.

SL blinks — Camera is in silhouette exposure mode; turn off your Speedlight flash unit.


N90s/F90X Instructions

Turning the Camera On and Off

Move the power switch located just behind the shutter release from the Off to the On position.

Note: When the camera is on, pressing the shutter release halfway turns on the exposure meter, viewfinder illumination, and, when appropriate, autofocusing. 

To turn power off, move the switch to the Off position.


Resetting the Camera to Its Default Settings

Simultaneously pressing the two reset buttons (labeled with a green •) for more than two seconds causes the N90s/F90X to revert to the following settings:

Single-frame film advance

Matrix metering pattern

Multi-Program (P) exposure mode

Wide focus area

No exposure compensation

Normal flash sync (unless Speedlight is set to rear-curtain)

MF-26 Multi-Control Back: Factory default settings cancel bracketing, multiple exposure, auto sequence, long exposure, interval timer, and focus priority. However, you can set your own custom reset options rather than use the factury default settings.

With Data Link: Custom reset settings are reloaded. (If you don’t want them to be reloaded, continue to hold the buttons down until CUSTOM blinks. Then press the two buttons once again.


Setting the Film Advance Mode

Hold down the drive button on the top left of the camera while rotating the command dial until the desired setting appears on the LCD panel:

  • [s in box] Single Frame—Press the shutter once for each exposure.
  • [L next to boxes] Continuous Low Speed —About 2 fps (frames per second) while the shutter is held down.
  • [H next to boxes] Continuous High Speed—About 4.3 fps while the shutter is held down.

The quoted frames per second are for shutter speeds of 1/250 second or faster in manual exposure and manual focus mode. The fastest rate for autofocus tracking is 4.1 fps.

Note: When imprinting data on film with the MF-26, don’t set film advance to k.


Setting the ISO Manually

Hold down the ISO button on the left top of the camera, and rotate the command dial to set the film speed (displayed on the LCD panel).


Setting the ISO Automatically with DX Encoding

1. Hold down the ISO button on the top left of the camera and rotate the command dial until the LCD displays DX.

2. Pressing the ISO button at any time will display the current ISO setting on the LCD in place of the frame number.


Loading Film

1. Set the ISO manually or set DX encoding.

2. Open the camera back using the two camera back releases on the left side of the camera body. 

3. Insert the film cartridge into the film chamber.

4. Pull the film leader across to the red index mark in take-up area.

5. Remove slack from the film leader so that it lies flat.

6. Close the camera back. 

7. Press the shutter release; the camera automatically advances film to the first frame. 


Rewinding  Film

Simultaneously press the two buttons labeled with the red O<< symbol (one is on the camera’s top left and the other is on the top right).


Setting the Metering Method

Hold down the matrix button on the left top of camera while rotating the command dial until the desired setting appears on the LCD panel:

  • Matrix — 8-segment evaluative metering is used. Requires AF or AI-P type lenses. With D-type lenses, the focusing distance is also taken into account. 
  • Center-Weighted — 75% of the meter’s sensitivity is concentrated in the central 12mm circle in the viewfinder.
  • Spot — 100% of the meter’s sensitivity is concentrated on the innermost 3mm ring in the viewfinder.


Setting the Focus Mode

Move the focus mode selector on the front of the camera, on the lower left, to:

S Single Servo AF—Uses focus-priority (shutter cannot be released until focus is achieved). 

Viewfinder symbols:

> or < Focus is in progress.

 Focus is locked; you need to refocus if the subject moves.

C Continuous Servo AF—Uses release priority (shutter can be released whether or not focus is achieved). Focus is continuously updated while the release button is pressed halfway. Focus is locked if the AF-L button is held down.

Viewfinder symbols:

> or < Focus is being sought.

Focus is achieved.

M Manual Focus—Electronic confirmation symbols appear in the viewfinder. 

Viewfinder symbols:

< Rotate the lens’ focus ring to the left; the subject is not in focus.

> Rotate the lens’ focus ring to the right; the subject is not in focus.

Focus is achieved.

> < (Blinking) Camera cannot autofocus.


Setting the Active Focusing Area

Hold down the focus area [o] button (in front of the command dial) while rotating the command dial until the desired setting appears on the LCD panel:

  • [box with [] ] Wide area AF selected
  • [box with • ] Spot area AF selected

Note: If the Speedlight is on, the N90s/F90X automatically switches to the spot area, regardless of what focusing area you set (the wide-area symbol blinks on the LCD panel if this is done). The camera reverts to your setting when you turn the Speedlight off or detach it.


Setting the Exposure Mode

Hold down the mode button on top left of the camera while rotating the command dial until the desired setting appears on the LCD panel:

  • P Multi-Program—Camera sets both the shutter speed and aperture; requires AF or AI-P lens.
  • S Shutter-Priority—You choose the shutter speed, the camera sets the aperture; requires AF or AI-P lens.
  • A Aperture-Priority—You choose the aperture, the camera sets the shutter speed.
  • M Manual—You choose both the aperture and shutter speed.

Or,

Hold down the Ps button on the top left of the camera while rotating the command dial until the desired vari-program symbol appears on the LCD panel:

  • PO Portrait mode—Sets a wide aperture to minimize depth of field.
  • RE Portrait mode with red-eye reduction—Same as portrait mode, except sets flash to red-eye reduction.
  • XF Hyperfocal mode—Sets a slow shutter speed and a narrow aperture to get subject and background in focus; does not set hyperfocal distance! A tripod is recommended.
  • LA Landscape mode—Virtually the same as XF, but intended for landscapes without a foreground subject. A tripod is recommended.
  • SL Silhouette mode—Underexposes the foreground subject; background should be 2 EV brighter to work effectively.
  • SP Sport mode—Sets a program that is biased towards a fast shutter speed.
  • CU Close-Up mode—Tries to set an aperture of f/4 or f/5.6.

To cancel these programs, hold down the mode button and set a regular exposure mode (P, S, A, or M).


Flexible Program (Program Shift)

In auto multi-program (P) mode, you can shift the programmed exposure in 1/3-stop increments to give you the creative effect you are looking for (e.g., greater depth of field). 

To shift the program, turn the command dial until the desired shutter speed-aperture combination is displayed on the LCD panel and viewfinder displays. P* appears in the LCD panel to confirm that the program has been shifted. 

After the shutter has been released, flexible program is cancelled.


Locking Exposure 

1. Use center-weighted or spot metering on an appropriate area.

Note: Although you can lock exposure settings using any metering mode, this function is most useful for metering on a very specific area. Center-weighted or spot metering modes offer the most control.

2. Lightly press the shutter release.

3. Lock exposure by sliding the AE-L button on the back of the camera.

4. Recompose, and press the shutter release fully to take the picture.


Exposure Compensation

Hold down the +/- button on the top right of the camera while rotating the command dial until the desired exposure compensation value appears on the LCD panel.

Compensation is indicated in 1/3 EV stops with a range of +/– 5 EV. A + value overexposes, a – value underexposes.

Example: Meter white snow and compensate by adding 2 stops of exposure. Without compensation, the meter sets exposure as though every subject were neutral gray. (A white subject is 2 stops brighter than neutral gray, therefore the exposure needs to be adjusted accordingly.)


Setting the Self-Timer

1. Hold down the self timer button on the top left of the camera, and rotate the command dial to set the duration of the delay in seconds (ranges from 2 to 30 seconds).

2. Close the eyepiece shutter with the switch to the left of the eyepiece.

3. Hold down the o button and press the shutter release.

4. The LED on the front of the camera blinks until the last 2 seconds prior to exposure, at which time it lights continuously.

If the camera is set for single servo AF (S), the self-timer will not start until focus is achieved. If the subject moves after the self-timer has begun counting down, the subject will be out of focus.

To cancel the countdown after the shutter release has been pressed, press the o button again before the shutter is fired.


Setting a Bulb Exposure

1. Hold down the mode button and rotate the command dial to select manual (M) exposure mode.

2. Rotate the command dial again to set bulb shutter speed (BVLB).

3. Set the desired aperture on the lens.

4. Press the shutter release for the duration of the exposure.

Consider using an MC-20, MC-30, ML-3, or other remote control release to prevent camera shake.

Note: When using an MF-26 Multi-Control Back or MC-20, long exposures may exhaust the camera’s batteries!


Setting Rear-Curtain Sync

1. To select a specific shutter speed, set the camera to shutter-priority (S) or manual (M) exposure mode. In multi-program (P) and aperture-priority (A) mode, slow sync is set automatically.

2. Set the Speedlight’s mode switch to TTL. (Rear-curtain sync can also be used in auto and manual flash modes, however only in A or M exposure modes.)

3. For an SB-24, -25, or -26: Set the flash unit’s sync switch to the REAR setting.

4. For other Nikon flashes: Hold the flash sync mode button on the top left of the camera and rotate the command dial until REAR appears in the LCD panel.

Note: Rear-curtain sync cannot be set with vari-program modes or used in conjunction with red-eye reduction.


Setting Slow-Sync Flash

1. Make sure the camera is set to multi-program (P) or aperture-priority (A) exposure mode. 

2. For the most automatic operation, set the Speedlight’s mode switch to TTL. (Manual and auto flash modes can also be used.)

3. Hold the | button on the top left of the camera and rotate the command dial until SLOW appears in the LCD panel.

4. A tripod is recommended to prevent camera shake.


Setting Red-Eye Reduction (SB-25, SB-26, SB-27, and SB-28)

Red-eye reduction can be set in M, P, A, and S modes. It is automatically set in Portrait program with red-eye reduction (Ps with RE). It cannot be set in any other vari-program.

1. Set the Speedlight’s mode switch to TTL.

2. Hold down the camera’s flash sync button and rotate the command dial until the red-eye indicator (double lightning symbols for the N90, an eye symbol for the N90s) appears in the LCD panel. 


Changing the Focusing Screen

1. Turn the camera off. Remove the lens.

2. Slip the tip of the tweezers provided with the new screen under the focusing screen’s release latch and pull outward. The latch is in the middle of the front edge of the screen.

3. Hold the tab on the screen with the tweezers and remove 

the screen.

4. Hold the tab on the replacement screen with the tweezers and insert the new screen in place.

5. Lock the screen holder in place by pushing upward.

Tip: The Type E screen features a lined grid that helps align horizons, reminds you of the rule-of-thirds points, and helps you detect converging lines, especially when using extreme wide-angle lenses. It is probably the most useful of the optional screens for general-purpose use.


Using AA Lithium Batteries in the N90s/F90X

Nikon now allows use of AA lithium batteries in the N90s/F90X without voiding the warranty. However, note that the use of the ML-3 module is not recommended if you’re using AA lithium batteries with this camera. The ML-3 draws its power from the camera and cannot accept the transient high voltage of AA lithium batteries. 

Note: This warning doesn’t apply to CR3 lithium batteries used in the optional MB-10 accessory grip.


N90s/F90X Multi-Program (P) Mode Settings 

(at ISO 100)

Exposure Value — Lens <85mm — Lens 85-210mm — Lens >210mm

  • EV0 — f/1.4 at 2 secs — f/1.4 at 2 secs — f/1.4 at 2 secs
  • EV2 — f/1.4 at 1/2 sec — f/1.4 at 1/2 sec — f/1.4 at 1/2 sec
  • EV4 — f/1.4 at 1/8 — f/1.4 at 1/8 — f/1.4 at 1/8
  • EV6 — f/2 at 1/15 — f/1.4 at 1/30 — f/1.4 at 1/30
  • EV8 — f/2.8 at 1/30 — f/2 at 1/60 — f/1.4 at 1/125
  • EV10 — f/4 at 1/60 — f/2.8 at 1/125 — f/2 at 1/250
  • EV12 — f/5.6 at 1/125 — f/4 at 1/250 — f/2.8 at 1/500
  • EV14 — f/8 at 1/250 — f/5.6 at 1/500 — f/4 at 1/1000
  • EV16 — f/11 at 1/500 — f/8 at 1/1000 — f/5.6 at 1/2000
  • EV18 — f/16 at 1/1000 — f/11 at 1/2000 — f/8 at 1/4000
  • EV20* — f/22 at 1/2000 — f/16 at 1/4000 — f/11 at 1/8000
  • EV22* — f/32 at 1/4000 — f/22 at 1/8000 — f/22 at 1/8000

*Exceeds limit of autofocus capability.

Note: If the lens being used has a smaller maximum aperture than shown above, shutter speeds will be slower than shown in order to maintain correct exposure.


Nikkor Lenses That Can’t Be Used with the N90s/F90x

Lens — Comments

  • AF Nikkor lenses for F3AF — Calculate exposure incorrectly
  • Non-AI lenses — Camera requires AI coupling
  • 6mm f/5.6 — Lens requires mirror to be locked up
  • 10mm f/5.6 — Lens requires mirror to be locked up
  • 28mm f/4 PC — Serial numbers 180900 and below need modification
  • 35mm f2.8 PC — Serial numbers 851001 to 906200 need modification
  • 80mm f/2.8 — Calculates exposure incorrectly
  • 180-600mm f8 ED — Serial numbers 174041 to 174180 incompatible
  • 200-600mm f/9.5 — Serial numbers 280001 to 301922 incompatible
  • 200mm f/3.5 IF — Calculates exposure incorrectly
  • 360-1200mm f/11 ED — Serial numbers 174031 to 174127 incompatible
  • 400mm f/5.6 — Doesn’t work with Focusing Unit AU-1
  • 600mm f/5.6 — Doesn’t work with Focusing Unit AU-1
  • 1000mm f/11 — Reflex Serial numbers 142361 to 143000 need modification
  • 2000mm f/11 — Reflex Serial numbers 200111 to 200310 need modification
  • AF TC-16 Calculates exposure incorrectly


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