Nikon Z6 vs Sony Alpha 7

      Disclosure: We earn money from the affiliate links to products associated with content in this article.

      Overview

      In this comparison, we will evaluate the Nikon Z6 and the Sony Alpha 7, highlighting the advantages of each over the other, discussing their pros and cons, shared strengths and weaknesses, and providing a rating based on their available features and specifications to assist you in choosing the one that best suits your needs.

      Nikon Z6 was introduced in August 2018 and Sony Alpha 7 was introduced in January 2014. Let us first list highlights of the models.

      Nikon Z6 Highlights

      • 24.5 MP Full Frame BSI-CMOS Sensor
      • 100 - 51,200 Native ISO
      • 273 Focus Points
      • 5-Axis Image Stabilization
      • 3.2" 2,100k dot Tilting Screen
      • 0.5" 3,690k dot Electronic Viewfinder
      • 12.0 fps Continuous Shooting
      • 3840 x 2160 Video Shooting
      • 30 min Video Recording Limit
      • Built-In Wi-Fi
      • Wheather Sealed Body

      Sony Alpha 7 Highlights

      • 24.3 MP Full Frame CMOS Sensor
      • 50 - 25,600 Native ISO
      • 117 Focus Points (117 Cross-type)
      • 3.0" 1,230k dot Tilting Screen
      • 2,359k dot Electronic Viewfinder
      • 5.0 fps Continuous Shooting
      • 1920 x 1080 Video Shooting
      • 30 min Video Recording Limit
      • Built-In Wi-Fi
      • Wheather Sealed Body

      Now that we've looked at the most essential specifications and gained a basic understanding of these cameras, we can delve into more details and see the differences between them.

      Pros and Cons

      In this section we present pros and cons of Nikon Z6 and Sony Alpha 7.

      PROS

      Nikon Z6

      Sony Alpha 7

      •   Video Capture
      •   Large Sensor
      •   51,200 Highest Native ISO
      •   273 Focus Points
      •   Touch-to-Focus
      •   Face Detection
      •   Live View Autofocus
      •   Animal Eye Detection
      •   Image Stabilization
      •   Touch Screen
      •   Large Screen - 3.2"
      •   High Resolution Screen - 2,100k dot
      •   Large Viewfinder - 0.5"
      •   High Max Shutter Speed (Mechanical or 1st Curtain) - 1/8000 sec
      •   High DxO Overall Score - 95
      •   High Video Resolution - 3840 x 2160
      •   No crop on 4K Videos
      •   Webcam Functionality
      •   High USB Speed
      •   HDMI Output
      •   Built-In Wi-Fi
      •   Built-In Bluetooth
      •   Environmental Sealing
      •   USB Charging
      •   Orientation Sensor
      •   Video Capture
      •   Large Sensor
      •   50 Lowest Native ISO
      •   117 Focus Points
      •   25 Cross-type Focus Points
      •   Face Detection
      •   Live View Autofocus
      •   High Max Shutter Speed (Mechanical or 1st Curtain) - 1/8000 sec
      •   High DxO Overall Score - 90
      •   HDMI Output
      •   Built-In Wi-Fi
      •   Environmental Sealing
      •   Light - 474 g (1.04 lb / 16.72 oz)
      •   Orientation Sensor

      CONS

      Nikon Z6

      Sony Alpha 7

      •   Low Video Recording Limit
      •   No Built-in GPS
      •   Short Battery Life - 330 shots
      •   No Image Stabilization
      •   Low Video Resolution - 1920 x 1080
      •   Low Video Recording Limit
      •   No Built-in GPS
      •   No Built-In Bluetooth
      •   Short Battery Life - 340 shots


      And here are some specifications which fall into average criteria and are neither in PROs nor in CONs category:

      AVERAGE

      Nikon Z6

      Sony Alpha 7

      •   Price
      •   Sensor Resolution - 24.5 Megapixel
      •   100 Lowest Native ISO
      •   -6 EV Min AF Detection
      •   Tilting Screen
      •   Viewfinder Resolution - 3,690k dot
      •   Max Continuous Shooting - 12.0 fps
      •   Max Flash Sync Speed - 1/200 sec
      •   Weight - 675 g (1.49 lb / 23.81 oz)
      •   Price
      •   Sensor Resolution - 24.3 Megapixel
      •   25,600 Highest Native ISO
      •   Tilting Screen
      •   Screen Size - 3.0"
      •   Screen Resolution - 1,230k dot
      •   Viewfinder Resolution - 2,359k dot
      •   Max Continuous Shooting - 5.0 fps
      •   Max Flash Sync Speed - 1/250 sec

      Advantage of Nikon Z6

      This section shows those features and specifications which are the reason to choose Nikon Z6 over Sony Alpha 7.

      Nikon Z6 vs Sony Alpha 7
      Sensor Type BSI-CMOS vs CMOS
      Higher Sensor Resolution 24.5 Megapixel vs 24.3 Megapixel
      Higher Native ISO 51,200 vs 25,600
      Max Image Resolution 6048 x 4024 vs 6000 x 4000
      More Focus Points 273 vs 117
      Touch-to-Focus vs
      Tracking Autofocus vs
      Animal Eye Detection vs
      Image Stabilization 5-Axis Sensor Shift vs
      Touch Screen vs
      Larger Screen 3.2" vs 3.0"
      Higher Resolution Screen 2,100k dot vs 1,230k dot
      Top LCD Screen vs
      Higher Viewfinder Magnification (35mm equivalent) 0.80x vs 0.71x
      Higher Resolution Viewfinder 3,690k dot vs 2,359k dot
      Higher Max Continuous Shooting 12.0 fps vs 5.0 fps
      Average Metering vs
      Higher DxO Low Light ISO 3299 vs 2248
      Higher DxO Color Depth 25.3 vs 24.8
      Higher DxO Dynamic Range 14.3 vs 14.2
      Higher DxO Overall Score 95 vs 90
      Higher Video Resolution 3840 x 2160 vs 1920 x 1080
      Higher USB Speed USB 3.2 Gen 1x1 (5 GBit/sec) vs USB 2.0 (480 Mbit/sec)
      Built-In Bluetooth vs

      Check out other cameras which are frequently compared to Nikon Z6.

      Advantage of Sony Alpha 7

      This section shows those features and specifications which are the reason to choose Sony Alpha 7 over Nikon Z6.

      Nikon Z6 vs Sony Alpha 7
      Cheaper $1995 (body only), $2599 (w/24-70 F4 lens) vs $1699.99 / £1299 (body only), $1999.99 / £1549 (with 28-70mm F3.5-5.6 lens)
      Lower Native ISO 100 vs 50
      Higher Flash Sync Speed 1/200 sec vs 1/250 sec
      Lighter 675 g (1.49 lb / 23.81 oz) vs 474 g (1.04 lb / 16.72 oz)
      Longer Battery Life 330 shots vs 340 shots

      Check out other cameras which are frequently compared to Sony Alpha 7.

      Common Strengths and Weaknesses

      We already listed pros and cons of each model. However, you may also find useful to look at their common strengths and weaknesses shown side-by-side.

      STRENGTHS Nikon Z6 Sony Alpha 7
        Video Capture
        Large SensorFull FrameFull Frame
        Many Focus Points273117
        Face Detection
        Live View Autofocus
        High Max Shutter Speed (Mechanical or 1st Curtain)1/8000 sec1/8000 sec
        High DxO Overall Score9590
        HDMI Output Mini Micro
        Built-In Wi-Fi
        Environmental Sealing
        Orientation Sensor
      WEAKNESSES Nikon Z6 Sony Alpha 7
        Low Video Recording Limit30 min - 60 fps or less
      3 min - 120/100 fps
      30 min
        No Built-in GPS
        Short Battery Life330 shots340 shots

      Screen and Viewfinder

      Screen

      Nikon Z6 has a 3.2" screen with 2,100k dot resolution and Sony Alpha 7 has a 3.0" screen with 1,230k dot resolution. Both have Tilting screens. Tilting screen makes cameras very useful for photography purposes but not so useful for video shooting. Nikon Z6 also features touchscreen which has advantages such as easy menu navigation, intuitive controls, quick setting adjustment and most importantly a Touch-to-Focus functionality allowing users to select a specific point on the screen where they want the camera to focus. This feature can be helpful for achieving precise focus in both photo and video recording.

      Image cannot be displayed

      Sony Alpha 7 with Tilting screen


      Viewfinder

      Nikon Z6 has a built-in 0.5" Electronic viewfinder with 3,690k dot resolution and Sony Alpha 7 has a built-in Electronic viewfinder with 2,359k dot resolution. They both have 100% coverage.

      Sensor

      Nikon Z6 features a 24.5 megapixel Full Frame BSI-CMOS sensor with dimensions of 35.9 x 23.9 mm and a total area of 858 mm2. Its native ISO range is 100 - 51,200 and expands to 50 - 204,800 in boosted mode. Sony Alpha 7 features a 24.3 megapixel Full Frame CMOS sensor with dimensions of 35.8 x 23.9 mm and a total area of 571.2 mm2. Its native ISO range is 50 - 25,600.

      Nikon Z6 has BSI-CMOS sensor, short for Backside Illuminated Complementary Metal-Oxide-Semiconductor sensor. In traditional CMOS sensors, the wiring and circuitry are located on the front side of the sensor, which can block some of the incoming light. BSI technology flips this design by placing the photosensitive elements (pixels) on the backside of the sensor, allowing more light to reach the pixels. This significantly enhances light sensitivity and improves low-light performance. BSI-CMOS sensors are particularly effective in low-light conditions, as they can capture more light, resulting in brighter and less noisy images. This makes them well-suited for indoor and night photography. BSI-CMOS sensors deliver a higher SNR and reduced cross-talk.


      Here is a sensor size comparison chart where you can see how different sensors compare with each other:

      Sensor size chart
      Sensor Dimensions Area Aspect Ratio Crop Factor
      Image cannot be displayedMedium Format44 x 33 mm1452 mm24:30.79x
      Image cannot be displayedFull Frame36 x 24 mm864 mm23:21x
      Image cannot be displayedAPS-H27 x 18 mm486 mm23:21.3x
      Image cannot be displayedAPS-C23.6 x 15.6 mm368.2 mm23:21.5x
      Image cannot be displayedAPS-C (Canon)22.3 x 14.9 mm332.3 mm23:21.6x
      Image cannot be displayedMicro Four Thirds17.4 x 13 mm226.2 mm24:32x
      Image cannot be displayed1-inch13.2 x 8.8 mm116.2 mm23:22.7x
      Image cannot be displayed1/1.7-inch7.44 x 5.58 mm41.5 mm24:34.7x
      Image cannot be displayed1/2.3-inch6.17 x 4.55 mm28.1 mm24:35.6x

      Photography Features

      Nikon Z6 is equipped with EXPEED 6 processor and can take pictures up to 6048 x 4024 resolution. It can also take pictures with lower resolution like 3936 x 2624 (DX crop), 4016 x 4016 (1:1), 6048 x 3400 (16:9) with 1:1, 5:4, 3:2, 16:9 aspect ratios. Sony Alpha 7 is equipped with BIONZ X processor and can take pictures up to 6000 x 4000 resolution. It can also take pictures with lower resolution like 6000 x 3376, 3936 x 2624, 3936 x 2216, 3008 x 1688, 3008 x 2000 with 3:2, 16:9 aspect ratios.


      Lens Mount

      Nikon Z6 has Nikon Z lens mount and Sony Alpha 7 has Sony E lens mount. Due to their Full Frame sensor their crop factor (also called lens multiplier) is equal to 1x. This means that a 35mm equivalent focal length of the mounted lens will be equal to its actual focal length.


      In-Body Image Stabilization on Nikon Z6

      Nikon Z6 has a built-in 5-Axis Sensor Shift in-body image stabilization (IBIS) with 5 stops of compensation. This means that you are still getting vibration reduction when camera is paired with non-image stabilizied lenses. It also works with lenses with optical image stabilization and in combination can achieve even better compensation.

      Connectivity, Battery and Storage

      Built-in Wi-Fi

      Cameras have built-in Wi-Fi (Wi-Fi 5 802.11ac/b/g/n 2.4/5 GHz on Nikon Z6) which allows to easily transfer photos and videos from the camera to other Wi-Fi-enabled devices, such as smartphones, tablets, printers, or computers. This eliminates the need for cables and allows for quick and convenient media sharing and social media integration. It gives you the ability to control your camera remotely using a smartphone or tablet. This is particularly useful for taking self-portraits, group shots, or capturing images in challenging conditions without having to touch the camera. Firmware updates can also be downloaded and installed wirelessly.
        Check out the cameras in our database that have built-in WiFi.


      Bluetooth on Nikon Z6

      Nikon Z6 has a built-in Bluetooth which lets you to connect the camera to a smartphone or a dedicated remote control device. This allows you to remotely trigger the camera, adjust settings and controls remotely through a paired mobile app. While Wi-Fi is generally faster for transferring larger files, Bluetooth can be used for small, selective transfers, it can provide real-time information about your camera's battery status, memory card capacity, and other key settings directly on your paired smartphone or smartwatch.
        Check out the cameras in our database that have built-in Bluetooth.


      NFC on Sony Alpha 7

      Sony Alpha 7 has Near Field Communication (NFC) technology which simplifies the process of pairing it with other NFC-enabled devices like smartphones or tablets. It allows to quickly transfer photos and videos or remotely control the camera from compatible device. NFC can also be used for authentication and security purposes. It can verify your identity before accessing certain features or transferring sensitive data. It can be used with NFC-enabled accessories as well, such as lenses, flashes and GPS devices.


      USB Inputs and HDMI Outputs

      Both models have USB inputs for data transfer. Nikon Z6 has a Mini HDMI and Sony Alpha 7 has a Micro HDMI connector for video signal output.


      Battery

      Nikon Z6 comes with EN-EL15b battery pack with battery life of 330 shots and Sony Alpha 7 comes with NP-FW50 battery pack with battery life of 340 shots.


      External Storage Slots

      Nikon Z6 has a single CFexpress Type B / XQD card slot. Sony Alpha 7 has a single SD/SDHC/SDXC, Memory Stick Duo/Pro Duo/Pro-HG Duo card slot.

      Other Features

      Shutter

      Nikon Z6 has Mechanical Focal Plane shutter and Electronic shutter. Sony Alpha 7 has Electronically controlled Vertical-traverse Focal-plane shutter. Shutter speed can go up to 1/8000 sec on Nikon Z6, and up to 1/8000 sec on Sony Alpha 7. Nikon Z6 can shoot continuously up to 12.0 fps. Sony Alpha 7 can shoot continuously up to 5.0 fps.


      Focusing

      Nikon Z6 has Hybrid phase-detection/contrast AF system with 273 focusing points and Sony Alpha 7 has Fast Hybrid AF (Phase-detection / Contrast-detection) system with 117 (25 cross-type) focusing points. Nikon Z6 has detection range from -6 to +19 EV.


      Exposure

      Exposure meterings of Nikon Z6 ranges from -4 to +17 EV and you can set the exposure compensation within the ±5 EV range. You can also do exposure lock, exposure bracketing and manual exposure adjustment on Nikon Z6 and exposure lock, exposure bracketing and manual exposure adjustment on Sony Alpha 7.


      Flash

      Cameras have no built-in flash but an external flash may be connected to both of them via Hot Shoe to Nikon Z6. The fastest flash synchronization speed is 1/200 sec on Nikon Z6 and 1/250 sec on Sony Alpha 7.

      Physical Parameters

      Nikon Z6 body has dimensions of 134 x 101 x 68 mm (5.28 x 3.98 x 2.68") and Sony Alpha 7 body has dimensions of 127 x 94 x 48 mm (5 x 3.7 x 1.89"). Nikon Z6 weighs 675 g (1.49 lb / 23.81 oz) and Sony Alpha 7 weighs 474 g (1.04 lb / 16.72 oz).

      Nikon Z6

      Sony Alpha 7

      134 mm

      101 mm

      Image cannot be displayed

      127 mm

      94 mm

      Image cannot be displayed


      101 mm

      Image cannot be displayed

      94 mm

      Image cannot be displayed


      68 mm

      Image cannot be displayed

      48 mm

      Image cannot be displayed

      Size comparisons of Nikon Z6 and Sony Alpha 7

      Nikon Z6 and Sony Alpha 7 for Different Types of Photography

      We give scores to the cameras for six types of photography based on their features and specifications. Let us see how suitable they are for each type of photography.

      Landscape Photography

      Nikon Z6

      Sony Alpha 7

      EXCELLENT
      88
      •   Large Sensor
      •   Touch Screen
      •   High Resolution Screen - 2,100k dot
      •   No Built-in GPS
      •   Environmental Sealing
      EXCELLENT
      85
      •   Large Sensor
      •   Screen Resolution - 1,230k dot
      •   No Built-in GPS
      •   Environmental Sealing

      Sports Photography

      Nikon Z6

      Sony Alpha 7

      GOOD
      81
      •   51,200 Highest Native ISO
      •   273 Focus Points
      •   Touch-to-Focus
      •   Face Detection
      •   Image Stabilization
      •   Touch Screen
      •   High Resolution Screen - 2,100k dot
      •   Viewfinder Resolution - 3,690k dot
      •   Max Continuous Shooting - 12.0 fps
      •   Short Battery Life - 330 shots
      •   Orientation Sensor
      AVERAGE
      69
      •   25,600 Highest Native ISO
      •   117 Focus Points
      •   25 Cross-type Focus Points
      •   Face Detection
      •   No Image Stabilization
      •   Screen Resolution - 1,230k dot
      •   Viewfinder Resolution - 2,359k dot
      •   Max Continuous Shooting - 5.0 fps
      •   Short Battery Life - 340 shots
      •   Orientation Sensor

      Wildlife Photography

      Nikon Z6

      Sony Alpha 7

      GOOD
      81
      •   51,200 Highest Native ISO
      •   273 Focus Points
      •   Touch-to-Focus
      •   Animal Eye Detection
      •   Image Stabilization
      •   Touch Screen
      •   High Resolution Screen - 2,100k dot
      •   Viewfinder Resolution - 3,690k dot
      •   Max Continuous Shooting - 12.0 fps
      •   Environmental Sealing
      •   Short Battery Life - 330 shots
      •   Orientation Sensor
      AVERAGE
      65
      •   25,600 Highest Native ISO
      •   117 Focus Points
      •   25 Cross-type Focus Points
      •   No Image Stabilization
      •   Screen Resolution - 1,230k dot
      •   Viewfinder Resolution - 2,359k dot
      •   Max Continuous Shooting - 5.0 fps
      •   Environmental Sealing
      •   Short Battery Life - 340 shots
      •   Orientation Sensor

      Portrait Photography

      Nikon Z6

      Sony Alpha 7

      EXCELLENT
      89
      •   Large Sensor
      •   273 Focus Points
      •   Touch-to-Focus
      •   Face Detection
      •   Image Stabilization
      •   Touch Screen
      •   Large Screen - 3.2"
      •   High Resolution Screen - 2,100k dot
      •   Max Flash Sync Speed - 1/200 sec
      •   Orientation Sensor
      GOOD
      81
      •   Large Sensor
      •   117 Focus Points
      •   25 Cross-type Focus Points
      •   Face Detection
      •   No Image Stabilization
      •   Screen Size - 3.0"
      •   Screen Resolution - 1,230k dot
      •   Max Flash Sync Speed - 1/250 sec
      •   Orientation Sensor

      Street Photography

      Nikon Z6

      Sony Alpha 7

      EXCELLENT
      89
      •   Large Sensor
      •   273 Focus Points
      •   Touch-to-Focus
      •   Image Stabilization
      •   Tilting Screen
      •   Touch Screen
      •   High Resolution Screen - 2,100k dot
      •   No Built-in GPS
      •   Environmental Sealing
      •   Weight - 675 g (1.49 lb / 23.81 oz)
      EXCELLENT
      85
      •   Large Sensor
      •   117 Focus Points
      •   25 Cross-type Focus Points
      •   No Image Stabilization
      •   Tilting Screen
      •   Screen Resolution - 1,230k dot
      •   No Built-in GPS
      •   Environmental Sealing
      •   Light - 474 g (1.04 lb / 16.72 oz)

      Travel Photography

      Nikon Z6

      Sony Alpha 7

      EXCELLENT
      85
      •   Image Stabilization
      •   Tilting Screen
      •   Touch Screen
      •   High Resolution Screen - 2,100k dot
      •   High Video Resolution - 3840 x 2160
      •   No crop on 4K Videos
      •   Low Video Recording Limit
      •   No Built-in GPS
      •   Environmental Sealing
      •   Weight - 675 g (1.49 lb / 23.81 oz)
      •   Short Battery Life - 330 shots
      GOOD
      84
      •   No Image Stabilization
      •   Tilting Screen
      •   Screen Resolution - 1,230k dot
      •   Low Video Resolution - 1920 x 1080
      •   Low Video Recording Limit
      •   No Built-in GPS
      •   Environmental Sealing
      •   Light - 474 g (1.04 lb / 16.72 oz)
      •   Short Battery Life - 340 shots

      Evaluations

      We evaluate Nikon Z6 and Sony Alpha 7 and give them scores of 84 and 72 out of 100 recpectively. We also give separate scores for 7 different categories according to the available features and specifications some of which are listed below. These evaluations are relative and may change each time a new camera is added to the database.


      Nikon Z6

      Sony Alpha 7

      OVERALL
      84
      OVERALL
      72

      Sensor

      Nikon Z6

      Sony Alpha 7

      GOOD
      81
      •   Large Sensor
      •   Sensor Resolution - 24.5 Megapixel
      •   100 Lowest Native ISO
      •   51,200 Highest Native ISO
      •   High DxO Overall Score - 95
      GOOD
      76
      •   Large Sensor
      •   Sensor Resolution - 24.3 Megapixel
      •   50 Lowest Native ISO
      •   25,600 Highest Native ISO
      •   High DxO Overall Score - 90

      Photo

      Nikon Z6

      Sony Alpha 7

      GOOD
      82
      •   Image Stabilization
      •   High Max Shutter Speed (Mechanical or 1st Curtain) - 1/8000 sec
      •   Max Continuous Shooting - 12.0 fps
      •   Max Flash Sync Speed - 1/200 sec
      AVERAGE
      65
      •   No Image Stabilization
      •   High Max Shutter Speed (Mechanical or 1st Curtain) - 1/8000 sec
      •   Max Continuous Shooting - 5.0 fps
      •   Max Flash Sync Speed - 1/250 sec

      Video

      Nikon Z6

      Sony Alpha 7

      GOOD
      71
      •   Image Stabilization
      •   High Video Resolution - 3840 x 2160
      •   No crop on 4K Videos
      •   Webcam Functionality
      •   Low Video Recording Limit
      BAD
      16
      •   No Image Stabilization
      •   Low Video Resolution - 1920 x 1080
      •   Low Video Recording Limit

      Focusing

      Nikon Z6

      Sony Alpha 7

      EXCELLENT
      92
      •   -6 EV Min AF Detection
      •   273 Focus Points
      •   Touch-to-Focus
      •   Face Detection
      •   Live View Autofocus
      •   Animal Eye Detection
      GOOD
      79
      •   117 Focus Points
      •   25 Cross-type Focus Points
      •   Face Detection
      •   Live View Autofocus

      Screen and Viewfinder

      Nikon Z6

      Sony Alpha 7

      EXCELLENT
      86
      •   Tilting Screen
      •   Touch Screen
      •   Large Screen - 3.2"
      •   High Resolution Screen - 2,100k dot
      •   Large Viewfinder - 0.5"
      •   Viewfinder Resolution - 3,690k dot
      GOOD
      74
      •   Tilting Screen
      •   Screen Size - 3.0"
      •   Screen Resolution - 1,230k dot
      •   Viewfinder Resolution - 2,359k dot

      Connectivity

      Nikon Z6

      Sony Alpha 7

      EXCELLENT
      96
      •   High USB Speed
      •   HDMI Output
      •   No Built-in GPS
      •   Built-In Wi-Fi
      •   Built-In Bluetooth
      EXCELLENT
      91
      •   HDMI Output
      •   No Built-in GPS
      •   Built-In Wi-Fi
      •   No Built-In Bluetooth

      Battery, Storage and Physical

      Nikon Z6

      Sony Alpha 7

      AVERAGE
      66
      •   Environmental Sealing
      •   Weight - 675 g (1.49 lb / 23.81 oz)
      •   Short Battery Life - 330 shots
      AVERAGE
      68
      •   Environmental Sealing
      •   Light - 474 g (1.04 lb / 16.72 oz)
      •   Short Battery Life - 340 shots


      For a full specification list please go to the specifications page:

      Amazon Affiliate Disclosure
      ZKelectronics is a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for website owners to earn advertising fees by advertising and linking to Amazon (.com, .co.uk, .ca, etc) and any other websites that may be affiliated with Amazon Service LLC Associates Program.