Determining How Much Space You Need

The amount of disk space you need depends on the specifications of the video format you are using for editing. In some cases, you can capture video at a lower quality (which saves disk space) for rough editing and then recapture only what you need at higher quality to create the finished movie. This process is known as offline/online editing. For more information, see Offline and Online Editing.

Know Your Shooting Ratio

Remember that when you start editing a movie, you need to capture much more media than you will use in the final movie. The ratio between the amount of footage you begin with and the final duration of the movie is called the shooting ratio. When you are estimating how much disk space you need for a project, calculate it based on the total amount of media you plan to capture and use during editing, not the intended duration of the final movie.

Planning for Additional Media Files

In addition to space for captured files and project files, you need extra space for render files, graphics, movie files created in other applications (such as animations), additional audio files, and so on. A loose rule of thumb to determine how much space you need is to multiply the amount of space needed for your finished program by five.

Ultimately, the amount of extra space you reserve depends on how much additional media you create during editing. For example, if you use hardly any effects, additional render files may not be a factor. If you are using only a few graphics files and little additional audio, these may not be a concern, either.

Keep in mind that although real-time effects don’t require additional drive space for rendering, you still need to render the effects at high quality for final output, so at that point you need enough disk space for render files.

Calculating Hard Disk Space Requirements

You can use the table below to estimate how much disk space you need for your project.

Video data transfer rates
30 sec.
1 min.
5 min.
10 min.
30 min.
60 min.
500 KB/sec.
OfflineRT (using Photo JPEG)
15 MB
30 MB
150 MB
300 MB
900 MB
1.8 GB
1 MB/sec.
Offline-quality M-JPEG
30 MB
60 MB
300 MB
600 MB
1.8 GB
3.6 GB
3.6 MB/sec.
DV-format video
HDV (1080i)
108 MB
216 MB
1.08 GB
2.16 GB
6.5 GB
13 GB
6 MB/sec.
Medium-quality M-JPEG
180 MB
360 MB
1.8 GB
3.6 GB
10.8 GB
21.6 GB
11.75 MB/sec.
352.5 MB
705 MB
3.4 GB
6.9 GB
20.7 GB
41.3 GB
12 MB/sec.
High-quality 2:1 M-JPEG
360 MB
720 MB
3.6 GB
7.2 GB
21.6 GB
43.2 GB
24 MB/sec.
Uncompressed SD video
720 MB
1.4 GB
7.2 GB
14.4 GB
43.2 GB
86.4 GB
121.5 MB/sec.
8-bit uncompressed 1080 29.97i HD video
3.6 GB
7.3 GB
36.5 GB
72.9 GB
218.7 GB
434.4 GB

Sample Calculation for Disk Space Requirements

Suppose you want to create a music video that’s approximately four minutes long using DV video for capture, editing, and output. Consider a shooting ratio of 15:1, meaning you shoot 15 times more footage than you will use in the final movie.

  1. Stage 1: Determining the Total Duration of Media Captured to Disk

    15 x 4 minutes = 60 minutes

  2. Stage 2: Determining the Data Rate Requirements for DV Media

    3.6 MB/sec. video data rate x 60 seconds = 216 MB/min.

  3. Stage 3: Calculating Disk Space Requirements for Media

    60 minutes x 216 MB/min. = 12,960 MB

    12,960 MB ÷ 1024 MB per GB = 12.66 GB

  4. Stage 4: Multiplying the Final Movie Length By a Safety Margin of 5 for Extra Files

    4 minutes x 216 MB/min. = 864 MB x 5 = 4320 MB

    4320 MB ÷ 1024 MB per GB = 4.22 GB

  5. Stage 5: Calculating the Total Disk Space Requirements

    12.66 GB + 4.22 GB = 16.88 GB

    Round your calculation up to 17 GB to be safe. This is the amount of disk space you’ll need for this one project. If you plan to work on multiple projects at the same time, estimate the amount for each project and add these numbers together.

    Note: These calculations are also important when planning how to archive your projects when they are finished, though many people choose to archive only the project file and not back up their media files. (Because the original footage is stored on tape, you can always recapture the footage if necessary.)