ARRI Data Calculator: Calculate Camera Sensor and Recording Specs


ARRI Data Calculator

Estimate Storage, Data Rates, and Workflow Requirements for ARRI Cameras

ARRI Data Calculator



Select the ARRI camera model you are using.


The physical width of the camera’s sensor.



The physical height of the camera’s sensor.



Horizontal resolution of the recorded image.



Vertical resolution of the recorded image.



Frames per second recorded.



Number of bits per color channel (e.g., 10, 12, 14).


The compression format used for recording.


Total planned recording time in minutes.


Calculation Results

— GB
— Mbps: Estimated Data Rate
— GB: Uncompressed Frame Size
— mm²: Sensor Area

Codec Factor: —
Bits per pixel: —

How it’s calculated:

1. Sensor Area = Sensor Width × Sensor Height

2. Bits per Pixel = (Bit Depth / 3) * 3 (for RGB) or Bit Depth (for ProRes 4444 which uses subsampling or ProRes RAW)

3. Uncompressed Frame Size = (Resolution Width × Resolution Height × Bits per Pixel) / 8 / 1024 (for GB)

4. Codec Factor: ARRIRAW is uncompressed (factor=1). ProRes applies compression (e.g., ProRes 4444 XQ ~ 500 Mbps for 4K, varies by resolution and frame rate, simplified here by a general factor). For simplicity, we use a fixed data rate for ProRes or a calculated rate for ARRIRAW.

5. Data Rate (Mbps): For ARRIRAW, it’s (Uncompressed Frame Size in bits × Frame Rate) / 1,000,000. For ProRes, a typical rate is used based on the model/settings (simplified here).

6. Total Storage (GB) = (Data Rate in Mbps × Recording Duration in minutes × 60 seconds/minute) / 8 / 1024 (for GB).

Note: ARRIRAW data rates are highly variable based on image content. ProRes rates are more predictable but also vary by specific ProRes variant and resolution. This calculator provides estimates.

Data Rate vs. Recording Time Comparison

Data Rate (Mbps)
Total Storage (GB)

Visualizing how data rate impacts total storage needs over different recording durations.

Key Camera Specifications by Model
Camera Model Typical Sensor Size (mm) Native Resolution Common Codecs ARRIRAW Data Rate (approx.)
ALEXA Mini LF 36.70 x 25.74 4.5K (4449×3096) ARRIRAW, ProRes ~3.2 GB/min (HQ)
ALEXA LF 36.70 x 25.74 4.5K (4449×3096) ARRIRAW, ProRes ~3.2 GB/min (HQ)
ALEXA Mini 28.20 x 18.80 2.8K (3168×1778) ARRIRAW, ProRes ~1.4 GB/min (HQ)
ALEXA 65 54.12 x 25.59 6.5K (6560×3100) ARRIRAW ~8.0 GB/min (HQ)
AMIRA 28.20 x 18.80 3.2K (3414×2198) ProRes N/A (ProRes Only)

What is ARRI Data Calculation?

ARRI data calculation refers to the process of estimating the amount of digital information generated by ARRI cinema cameras during recording. This involves understanding various parameters such as sensor size, resolution, frame rate, bit depth, and codec. Effectively calculating ARRI data is crucial for filmmakers and production teams to plan and manage their workflow, ensuring they have adequate storage capacity, sufficient bandwidth for data transfer, and appropriate hardware for post-production.

It’s not just about raw file size; it’s about understanding the throughput of data from the camera sensor through the internal processing and recording media. This helps in budgeting for media, planning for ingest and backup, and optimizing the overall efficiency of a digital cinematography project. Accurate ARRI data calculation minimizes surprises and costly delays during production and post-production.

Who should use it:

  • Cinematographers and Directors of Photography
  • Camera Assistants and Technicians
  • Digital Imaging Technicians (DITs)
  • Production Managers and Line Producers
  • Post-production Supervisors and Editors
  • Anyone involved in planning ARRI camera shoots

Common misconceptions:

  • “All ARRI RAW files are the same size.”: This is incorrect. ARRI RAW (ARRIRAW) file sizes vary significantly based on the specific camera model, recording mode (e.g., HQ, standard), and even the content of the image itself due to inherent data compression techniques within ARRIRAW.
  • “Calculating data is just about multiplying resolution by frame rate.”: While these are key factors, bit depth, codec choice (especially compressed vs. uncompressed), and specific camera processing play a massive role. ARRIRAW, while visually lossless, is not strictly uncompressed in the way a TIFF or BMP is.
  • “Storage is the only concern.”: Data rate (megabytes or gigabits per second) is equally important. A high data rate can overwhelm recording media, network transfer speeds, and editing systems, even if total storage capacity is sufficient.

ARRI Data Formula and Mathematical Explanation

The core of ARRI data calculation involves determining the data generated per frame and then scaling it up based on frame rate and recording duration. For codecs like ARRIRAW, which are visually lossless but still employ some form of data optimization, the calculation is complex. For compressed formats like ProRes, predictable data rates are often published.

Step-by-step derivation (Simplified Model):

We’ll use a simplified model for ARRIRAW and a standard data rate for ProRes for estimation.

1. Calculate Sensor Area:

This gives a sense of the physical capture surface.

Sensor Area (mm²) = Sensor Width (mm) × Sensor Height (mm)

2. Calculate Pixels per Frame:

The total number of pixels captured in a single frame.

Total Pixels = Resolution Width (pixels) × Resolution Height (pixels)

3. Determine Bits per Pixel:

This depends heavily on the bit depth and color subsampling. For simplicity in estimation:

  • For ARRIRAW (Typically 12-bit or 14-bit, full color): Assume 12 bits per pixel as a common baseline for calculation. Some modes might use more.
  • For ProRes 4444 / XQ (12-bit): Also assume 12 bits per pixel for calculation, though the compression makes the final file size different.

Note: ARRIRAW’s internal compression means the effective bits per pixel can vary. The calculator uses a simplified approach.

4. Calculate Uncompressed Frame Size (in bits):

This is the theoretical size if no compression were applied.

Uncompressed Frame Size (bits) = Total Pixels × Bits per Pixel

5. Calculate Uncompressed Frame Size (in Gigabytes):

Convert bits to Gigabytes for easier understanding.

Uncompressed Frame Size (GB) = (Uncompressed Frame Size (bits)) / (8 bits/byte × 1024 bytes/KB × 1024 KB/MB × 1024 MB/GB)

6. Determine Data Rate (Megabits per second – Mbps):

This is the crucial metric for workflow planning.

  • For ARRIRAW: A common estimation method is to use published average data rates for specific recording modes (e.g., ARRIRAW HQ). These are often provided by ARRI in GB per minute. We convert this to Mbps.

    Example conversion: 3.2 GB/min → (3.2 * 1024 * 1024 * 1024 bytes/GB * 8 bits/byte) / (60 seconds/min) / 1,000,000 bits/Megabit ≈ 457 Mbps.

    The calculator uses simplified representative values.
  • For ProRes: ARRI publishes approximate data rates for ProRes codecs at various resolutions and frame rates. These are generally more stable than ARRIRAW. The calculator uses these established rates.

7. Calculate Total Storage Needed (in Gigabytes – GB):

The final calculation for total capacity.

Total Storage (GB) = (Data Rate (Mbps) × Recording Duration (minutes) × 60 seconds/minute) / (8 bits/byte × 1024 MB/GB)

Variables Table:

Variable Meaning Unit Typical Range / Values
Sensor Width Physical width of the camera’s image sensor. mm 28.20 (Mini/Amira) to 54.12 (Alexa 65)
Sensor Height Physical height of the camera’s image sensor. mm 18.80 (Mini/Amira) to 31.00 (Alexa 65)
Resolution Width Number of horizontal pixels in the recorded image. pixels ~1920 (HD) to ~6560 (6.5K)
Resolution Height Number of vertical pixels in the recorded image. pixels ~1080 (HD) to ~3100 (6.5K)
Frame Rate Number of frames captured per second. fps 1 to 120+ (camera dependent)
Bit Depth Number of distinct tonal values per color channel. bits 10, 12, 14
Codec Compression standard used for recording. N/A ARRIRAW, ProRes (4444, 4444 XQ, etc.)
Recording Duration Total time footage is captured. minutes 1 to 120+
Data Rate Speed at which data is generated/recorded. Mbps ~150 Mbps (ProRes LT) to 4000+ Mbps (ARRIRAW)
Total Storage Total capacity required for the recorded footage. GB / TB Highly variable, depends on duration and data rate.

Practical Examples (Real-World Use Cases)

Example 1: High-End Feature Film Shoot (ALEXA Mini LF)

Scenario: A DP is shooting a feature film using an ALEXA Mini LF in ARRIRAW HQ mode. They plan for a demanding day of principal photography where continuous recording might occur.

  • Camera Model: ALEXA Mini LF
  • Sensor Width: 36.70 mm
  • Sensor Height: 25.74 mm
  • Resolution Width: 4449 pixels
  • Resolution Height: 3096 pixels
  • Frame Rate: 25 fps
  • Bit Depth: 12-bit (typical for ARRIRAW HQ)
  • Codec: ARRIRAW
  • Recording Duration: 60 minutes (for a potential full day’s worth of continuous recording)

Calculation using the tool:

  • Estimated Data Rate: ~ 1900 Mbps (This value varies greatly with content but HQ mode aims for consistency)
  • Uncompressed Frame Size: ~ 1.6 GB
  • Total Storage: ~ 114 GB

Interpretation: For just one hour of footage in ARRIRAW HQ from the ALEXA Mini LF at 25fps, the production needs to account for approximately 114 GB of storage. This means a single 512GB CFast 2.0 card can hold roughly 4.5 hours of footage. The high data rate (around 1900 Mbps) also implies the need for fast media cards and a robust workflow for offloading data.

Example 2: Commercial Shoot with ProRes (AMIRA)

Scenario: A commercial production is using an AMIRA, favoring the efficiency and compatibility of ProRes. They need to estimate media requirements for a day of shooting.

  • Camera Model: AMIRA
  • Sensor Width: 28.20 mm
  • Sensor Height: 18.80 mm
  • Resolution Width: 3168 pixels (Common for 2.8K ARRIRAW, AMIRA often records ProRes at different resolutions, let’s assume ProRes 4K UHD for this example: 3840 pixels)
  • Resolution Height: 2160 pixels (For ProRes 4K UHD)
  • Frame Rate: 30 fps
  • Bit Depth: 12-bit (ProRes 4444 XQ)
  • Codec: ProRes 4444 XQ
  • Recording Duration: 120 minutes (Spread across multiple takes)

Calculation using the tool (adjusting inputs for ProRes 4K UHD context):

(Note: The tool might need specific presets or manual input for exact ProRes rates. Assuming a typical ProRes 4444 XQ 4K UHD rate for calculation)

  • Estimated Data Rate: ~ 500 Mbps (Approximate for ProRes 4444 XQ at 4K UHD, 30fps)
  • Total Storage: ~ 375 GB

Interpretation: Shooting in ProRes 4444 XQ on the AMIRA at 4K UHD requires a significant amount of data, around 375 GB for 2 hours of footage. This translates to needing multiple high-capacity SSDs or CFast cards. The advantage here is the more predictable data rate compared to ARRIRAW, simplifying media planning. Editors will find ProRes easier to handle in post-production compared to ARRIRAW.

How to Use This ARRI Data Calculator

This calculator is designed to give you a quick and accurate estimate of the data generated by ARRI cameras. Follow these simple steps:

  1. Select Camera Model: Choose your specific ARRI camera from the dropdown menu. This will pre-fill some typical sensor dimensions.
  2. Input Sensor Dimensions (if needed): Verify or input the exact sensor width and height in millimeters. This is often available in the camera manual or technical specifications.
  3. Enter Resolution: Input the exact horizontal and vertical resolution (in pixels) you intend to record at.
  4. Set Frame Rate: Specify the frames per second (fps) for your recording.
  5. Choose Bit Depth: Select the bit depth (e.g., 10-bit, 12-bit, 14-bit) according to your recording settings.
  6. Select Codec: Choose the recording codec: ARRIRAW for the highest quality and flexibility, or ProRes for a balance of quality and efficiency.
  7. Specify Recording Duration: Enter the total planned recording time in minutes. This is not necessarily shoot duration but the time you expect to be capturing footage.
  8. View Results: The calculator will automatically update the results in real-time.

How to Read Results:

  • Primary Result (Total Storage): This is the main output, displayed prominently. It shows the total estimated storage space required in Gigabytes (GB) for the specified recording duration.
  • Estimated Data Rate: This shows the average data throughput in Megabits per second (Mbps) required to sustain the recording. Crucial for checking media speed and transfer times.
  • Uncompressed Frame Size: The theoretical size of a single frame before any compression is applied. Useful for understanding the raw data volume per image.
  • Sensor Area: The physical size of the sensor, relevant for understanding field of view characteristics.
  • Assumptions: Details like the Codec Factor and Bits per Pixel used in the calculation are shown for transparency.
  • Formula Explanation: A breakdown of the calculations is provided for clarity.

Decision-Making Guidance:

  • Storage Planning: Use the Total Storage result to determine how many media cards (e.g., CFast, SSDs) you need and their capacities. Always have more capacity than calculated to be safe.
  • Media Speed: Compare the Estimated Data Rate against the specifications of your media cards. Ensure your cards can sustain the required write speed.
  • Workflow Efficiency: A high data rate necessitates faster transfer solutions from camera to workstation and potentially more powerful editing hardware.
  • Budgeting: Accurate data estimates help in budgeting for media, drives, and potential cloud storage or backup solutions.
  • Post-Production: Understanding the codec (ARRIRAW vs. ProRes) helps anticipate post-production requirements regarding software compatibility and hardware demands.

Key Factors That Affect ARRI Data Results

While the calculator simplifies many aspects, several real-world factors significantly influence the actual data generated by ARRI cameras:

  1. ARRIRAW Recording Mode: ARRI offers different ARRIRAW recording modes (e.g., HQ – High Quality, Standard, Medium). HQ mode generates significantly more data per frame than Standard mode, as it retains more image information and uses less aggressive compression. The calculator typically uses HQ as a baseline estimate.
  2. Image Content Complexity: Even within the same recording mode, ARRIRAW compression algorithms adapt to the image content. Scenes with high detail, noise, or rapid motion (like wind in trees or fast-moving water) will generate slightly more data than static, low-detail scenes. This is a key reason ARRIRAW data rates are estimates.
  3. ProRes Variant: ProRes comes in various flavors (LT, 422, 422 HQ, 4444, 4444 XQ). Each has a different compression ratio and data rate. ProRes 4444 XQ produces the highest quality and data rate within the ProRes family, approaching ARRIRAW quality in some aspects.
  4. Camera Sensor Format / Cropping: ARRI cameras often allow recording in different sensor formats or aspect ratios (e.g., Open Gate, 16:9, 4:3). Recording in a wider format like Open Gate at the sensor’s native resolution generally produces more data than recording in a more cropped or standard aspect ratio.
  5. Frame Rate Variations: While the calculator uses a specified frame rate, cameras can often record at higher frame rates (e.g., slow-motion). Doubling the frame rate generally doubles the data rate and total storage required for the same recording duration.
  6. Metadata Embedded in ARRIRAW: ARRIRAW files contain extensive metadata (camera settings, lens data, etc.). While this adds to the file size, it’s typically a small fraction compared to the image data itself but contributes to the overall file footprint.
  7. Data Corruption / Unusable Footage: In real-world scenarios, not all footage is usable. Media errors, accidental deletes, or takes that are discarded due to technical or performance issues mean the actual usable footage might be less than planned, but the storage must be available for the entire capture period.
  8. Media Overheads: Recording media (like CFast cards or SSDs) have their own file system overheads and may not always provide the absolute maximum theoretical write speeds consistently, especially when nearing full capacity.

Frequently Asked Questions (FAQ)

Q1: Is ARRIRAW truly uncompressed?

No, ARRIRAW is not strictly uncompressed like a BMP or TIFF file. It uses a sophisticated, visually lossless compression method (part of its proprietary format) that adapts to image content. This significantly reduces file size compared to a theoretical uncompressed RAW format while preserving maximum image quality and flexibility for grading.

Q2: How does ARRIRAW data rate vary with image content?

ARRIRAW’s compression is adaptive. Highly detailed or noisy scenes require more bits to represent accurately, thus increasing the data rate. Simple, clean scenes require fewer bits. This variability is why ARRIRAW data is often quoted as an average or for specific modes like ‘HQ’.

Q3: What’s the difference between ProRes and ARRIRAW for data calculation?

ARRIRAW is the camera’s native sensor data, offering maximum flexibility in post-production but generating larger files and higher data rates. ProRes is a high-quality, broadly compatible compressed video format. ProRes files are smaller and have more predictable data rates, making them easier to handle in terms of storage and editing, but offer less grading latitude than ARRIRAW.

Q4: Do I need faster media for ARRIRAW than ProRes?

Generally, yes. Because ARRIRAW typically has a higher data rate than most ProRes variants (especially at similar resolutions), you need media cards (like CFast 2.0 or Codex Capture Drives) that can sustain those higher write speeds reliably. ProRes offers more flexibility with media choices.

Q5: How much faster is ProRes 4444 XQ than ProRes 422 HQ?

ProRes 4444 XQ has a higher data rate than ProRes 422 HQ, typically by about 30-50%. It also supports higher bit depths (up to 12-bit) and RGB color channels, making it suitable for VFX work. ProRes 422 HQ is still very high quality but uses more aggressive compression.

Q6: Can I use this calculator for older ARRI cameras?

This calculator is designed for current and recent ARRI camera models. Older models might have different sensor sizes, resolutions, or recording options that could lead to inaccuracies. Always refer to the specific technical specifications for older cameras.

Q7: What does ’12-bit ARRIRAW’ mean in practice?

It refers to the camera’s ability to capture 12 bits of color information per color channel (Red, Green, Blue). This provides a wider dynamic range and smoother tonal gradations compared to 10-bit footage, offering more flexibility during color grading. 14-bit capture is also available in certain modes for even greater range.

Q8: How should I account for multiple camera shoots?

If you are using multiple cameras simultaneously, you need to multiply the estimated data rate and total storage by the number of cameras operating under similar settings. Ensure your infrastructure (e.g., network, storage servers) can handle the aggregated data throughput.

Q9: What is the impact of recording aspect ratio (e.g. 16:9 vs Open Gate) on data?

Recording in a wider aspect ratio like Open Gate (which uses more of the sensor’s pixels) will generate more data than recording in a narrower aspect ratio like 16:9, assuming the same frame rate and codec. This is because more pixels need to be processed and stored per frame.

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