Pentax 645Z Digital Medium Format Gear Guide

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The highest quality camera available at Media Loan.
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The Pentax 645Z is a digital medium format camera. It is equipped with a 51.4MP censor, which was designed without an anti-aliasing filter to maximize sharpness and details. Its wide ISO range provides low noise, low light capability, and the image processor allows for fast image capture.

It is the only one of its kind at Media Loan, and access to it is very limited. Only certain approved photography classes are permitted to use it. A proficiency test is required to use it, after users obtained their DSLR camera and 6D Digital camera.


Simply put, a medium format camera has a larger sensor than other standard DSLR cameras. A bigger sensor means bigger pixel size, which means better quality. The Pentax 645Z has 3-4x more frame surface than sensors equipped on Canon Rebel DSLRs, which means stills taken with the Pentax can be enlarged significantly without losing quality.

Medium format cameras also have no perspective distortion - images taken more closely resemble the way the human eye sees the real world. The field of view is much wider than other cameras with standard cropped sensors. Let's say you're shooting on a 6x7 medium format camera with a 50mm lens. If you compare your images to a 35mm camera (also with a 50mm lens), the field of view will be different. The medium format pictures will actually see what a 24mm lens on a 35mm camera would see. Simply put: the larger the format, the wider angle your lenses become. You can shoot a wide scene but it will have the "real-world" look of a lens with a longer focal length. The subject remains proportional and not "stretched-out".


43.8 x 32.8 mm CMOS

Color Depth
JPEG: 8 bits/channel RAW: 14 bits/channel

Effective Pixels / Total Pixels
51.4MP / 52.99MP

File Formats
Stills: RAW (PEF/DNG), TIFF, JPEG (Exif 2.30), DCF2.0 compliant
Video: MPEG-4 AVC/H.264 (MOV) *Motion JPEG (AVI) for Interval Movie Record

Image Resolution
JPEG: L (51M: 8256 x 6192), M (36M: 6912 x 5184), S (21M: 5376 x 4032), XS (3M:1920 x 1440)
RAW: L (51M: 8256 x 6192)
TIFF: L (51M: 8256 x 6192)

Video Resolution
Full HD: (1920x1080, 60i/50i/30p/25p/24p)
HD: (1280x720, 60p/50p/30p/25p/24p)

Lens Mount
Pentax 645AF2

Shutter Speeds
Auto: 1/4000 to 30 sec.
Manual: 1/4000 to 30 sec.

Burst Rate
3 fps, JPEG: up to 30 frames
RAW: up to 10 frames
TIFF: up to 12 frames

ISO Sensitivity
100 – 204,800


Pentax Front Parts
Pentax Back Parts
Pentax Bottom Parts
  • Pentax 645Z Digital Medium Format Camera
  • Batteries (2)
  • 128GB Memory Card
  • SMC Pentax-FA 645 1:2.8 75mm Prime Lens
  • SMC Pentax-A 645 1:4 120mm Macro Lens
  • Lens Hoods (2, Metal & Silicon)
  • Battery Charger

How to Use It



The diopter focuses the viewfinder to your individual eyesight to ensure that you obtain proper focus. YOU MUST PROPERLY ADJUST THE DIOPTER BEFORE FOCUSING WITH THE LENS. Also adjust the diopter for very operator.

To adjust the diopter:

  1. Ensure no lens is attached (you may confuse the focus of the lens with the focus of the viewfinder)
  2. Point the camera at a bright object, but NOT THE SUN
  3. Look through the viewfinder
  4. Turn the diopter adjustment ring until the focusing brackets in the viewfinder are in focus. Turn the ring clockwise for a negative value and counterclockwise for a positive value.


This monitor can be tilted to viewing preference.

  1. Hold the camera in one hand and the top of the monitor with the other.
  2. Slowly lower until it stops
  3. Hold the monitor to lift it upward
  4. Adjust the angle accordingly


Click images to enlarge.
Pentax controls front.png
Pentax controls back.png
  1. Shutter Release
  2. ISO
  3. EV Compensation
  4. Main switch: Move to turn the power on/off. The symbol of the right is Depth of Field Preview, and will display accurate focusing depending on aperture in the viewfinder.
  5. Front e-dial: Changes the values for camera settings such as exposure; switch menu categories; image selection
  6. Lens unlock: Press to detach the lens
  7. Metering Mode Dial: Changes the metering mode
  8. Lock: Temporarily disables e-dial and button operation
  9. AF (auto-focus) Area: Press to change the AF point
  10. Exposure Bracketing
  11. RAW/Fx: You can assign a function to this button
  12. Mode Dial Lock
  13. Mode Dial: Changes the exposure mode
  14. Stills/Movie Switch Dial: Switchings between still capture and move recording modes
  15. Rear e-dial: Changes the values to camera settings such as exposure; switch menu tabs; change camera settings; magnify images
  16. AF Mode Dial: Switches AF modes (AF.S/C)
  17. Mirror Up Dial: Enables shooting with the mirror raised
  18. Illumination: Illuminates LCD panel
  19. AE Lock: Locks exposure value; saves JPEG to RAW
  20. AF: Available for adjusting focus, instead of pressing shutter release halfway
  21. OK
  22. Four-way Controller: Displays the Drive Mode, Flash Mode, White Balance or Custom Image setup menu; move cursor or selected list item
  23. AF Point Change/Card Slow Switch: Press to enable changing AF point; switch memory cards in playback mode
  24. Green: Reset the values being adjusted; switches to ISO AUTO
  25. Live View/REC/Delete: Displays Live View image on monitor; stars/stops recording in movie move; delete images during playback
  26. INFO: Changes style of display on monitor
  27. MENU
  28. Playback


The Four-way Controller (22) is the main way to access major settings. Pressing the buttons on the Four-Way Controller will activate the following:

  • Top: Drive Modes
  • Bottom: Flash Modes
  • Right: Custom Image
  • Left: White Balance


In Standby or Live View, press the INFO button to access various camera settings, such as:

  • Highlight Correction: reduces occurence of overexposure.
  • Shadow Correction: reduces occurence of underexposure.
  • Distortion Correction: reduces distortion due to lens properties.
  • Lat-Chromatic-Ab Adjustment: reduces lateral chromatic abberations due to lens properties.
  • Peripheral Illumination Correction: reduces peripheral light fall-off occurring due to lens properties.
  • Diffraction Correction: corrects the diffraction when the aperture is small.
  • HDR: takes three consecutive images at three different exposure levels to create a single composite picture.
  • Memory card options: selects one of the two inserted memory card (Media Loan only provides one).
  • File format options: change the file format.
  • JPEG Resolutions: change the JPEG resolution.
  • Noise Reduction: High-ISO NR sets the noise reduction setting when shooting with a high ISO. Slow Shutter Speed NR sets how the noise reduction setting functions during long exposures.
  • AF Area: set the auto-focus area.
  • Focus Peaking (only when Live View is activated): emphasizes (sharpens) the outline of the subject in focus to make it easier to check for proper focus

Press INFO again to exit screen.

Now that you are in viewing mode, press INFO button to be given the option to select a preferred display screen:

  • Status Screen
  • Electronic Level
  • Display Off


Press the MENU button to change camera settings. Use the Four-Way Controller, Front e-dial and Rear e-dial to navigate.

  • Camera tabs: Here you can adjust settings such as memory card options, HDR, Preview settings, button customization, etc.
  • Video tab: Adjust movie capture settings, video exposure settings, etc.
  • Playback tab: Adjust image display options in playback mode
  • Wrench tabs: Make system adjustments such as date/time, LCD display options, etc. Also use to format memory cards. Always format the memory cards prior to return at Media Loan.


  1. Make sure the camera is off.
  2. Remove the body mount cap. Press down the Lens Unlock button (3) and remove cap.
  3. Align the lens mount index (red dots) on the body and lens, and turn the lens clockwise. Do not press the lens unlock at this time.

To remove: Turn the lens counterclockwise while holding down the lens unlock button.


There are many ways to change you exposure settings (shutter speed, aperture, ISO) with this camera. Use the below guide as a quick reference to control these settings. These can be used with or without Live View activated.

  • Shutter Speed: Front e-dial
  • Aperture: Rear e-dial
  • ISO: Press the ISO button, then adjust with Rear e-dial

Note: with the included lenses, the aperture can be changed on the aperture ring. To enable aperture manipulation in the camera, you must set the ring to A. To do this, press the button on the aperture ring and turn the ring to the green A position.


Auto-Focus (AF) cannot be used with the 120mm lens included in the kit. To enable AF with the 75mm prime, turn the switch on the lens from MF (manual focus) to AF.

  • To engage auto-focus, depress the Shutter Release halfway until the lens is done focusing. You can also use the AF button to auto-focus.
  • To change the area in which the camera is auto-focusing, hold down the AF Area button during Stand-by Mode (Live View deactivated) and scroll through the options with the Rear e-dial. Release, and use the Four-Way Controller buttons to change the position of the auto-focus area with the selected AF setting.
  • To change the position of the auto-focus without changing the AF area, press the AF Point Change button in Stand-by Mode and use the Four-Way Controller buttons. Press the AF Point Change button again to exit.


When Focus Peaking is on, the outline of the subject in focus is emphasized (sharpened). This makes it easier to check the focus. Focus peaking works in both AF and MF modes. To turn on focus peaking, press the INFO button and navigate to "Focus Peaking" when Live View is activated.


This camera has multiple white balance presets.
To change the white balance setting:

  1. Press the left button on the Four-Way Controller. The White Balance setting screen will appear on the monitor.
  2. Select your White Balance. The different preset settings have various options.

Fine-tuning presets: Press INFO when in white balance to pull up the fine-tuning menu. You can adjust Green-Magenta with the top/bottom controller buttons, or Blue-amber with the left and right controller buttons. The Green button resets the adjustment value to default. Press OK when done.


It is recommended to use custom white balance on any DSLR camera. The preset white balance options may come in handy, but only by setting a custom white balance can you be sure that the colors in your images will be accurate.

  1. With the camera on, fill the frame with a completely white object (such as a piece of paper) in the desired lighting.
  2. Access the white balance options as described above, and navigate to Custom.
  3. Push the Main Switch to the Preview selection. This will set your custom white balance using the white reference within the frame.


You can utilize this feature to change the desired picture style with different colors. If you do not want the camera to change the color of your images, set this to "Natural" (no color manipulation).

  1. Press the right button on the Four-Way Controller to pull up the Custom Image setting screen.
  2. Select the desired tone. Scroll through controller buttons to view options. You can engage the PREVIEW button to preview the background image with selected effect.
  3. Press INFO to pull up the parameter setting screen.
  4. Set the parameters. The top/bottom controller buttons selects parameter, the left/right controller buttons adjust the value, the Front e-dial switches contrast, the Rear e-dial switches sharpness, and the Green button resets the adjustment value to default.
  5. Press OK.


This camera has many exposure mode options. The recommended exposure mode for the majority of photography is M (Manual). P, Sv, Tv, Av, and TAv are all semi-automatic exposure modes and, when engaged, the camera will make certain exposure decisions for you (refer to chart below).

Use the Mode Dial to change the exposure mode setting.

Exposure modes.png


The Drive Mode refers to the capturing mode that images are taken. This camera has many different drive modes. Use the chart below to select your desired drive mode.

To change the drive mode, press the top button on the Four-way Controller and make your selection.

Drive modes.png


Metering refers to the built-in light meter in the camera. The light meter determines the amount of light coming into the lens. The Pentax 645Z has multiple metering modes. Use the chart below to select your desired metering mode.

Use the Metering Mode Dial, located near the Mode Dial, to switch between the three metering modes.



See Troubleshooting Media Equipment Guide for general information.

Similar Models at Media Loan

This is more advanced than our other DSLRs like the Canon 6D and Canon Rebel T6i. You need to be proficient in those cameras before getting to become proficient and use the Pentax 645Z