"If it can be written, or thought, it can be filmed..." STANLEY KUBRIC

VHS tape

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A VHS cassette contains a ½ inch (12.7 mm) wide magnetic tape wound between two spools, allowing it to be slowly passed over the various playback and recording heads of the video cassette recorder.

The tape speed is 3.335 cm/s for NTSC, 2.339 cm/s for PAL. A cassette holds a maximum of about 430 m of tape at the lowest acceptable tape thickness, giving a maximum playing time of about 3.5 hours for NTSC and 5 hours for PAL at "standard" (SP) quality.

VHS Videotape Running Times for NTSC, PAL and SECAM

Because VHS Videotape is marked in playing times as opposed to tape length, a lot of confusion arises as to why a PAL SECAM VHS E120 (2 hour) videotape will not give two hours of recording time when used on a US NTSC Video recorder.

The US T120 VHS videotape is 246 meters in length and will give 2 hours play time on an NTSC VCR. This same videotape used on a PAL VCR will give 2 hours & 49 minutes of play time.

Conversely, a UK E120 VHS videotape is 173 meters in length and will give 2 hours play time on a PAL VCR. The same tape used on an NTSC VCR will give only 1 hour & 26 minutes of play time.

An NTSC video player/recorder uses tape at a higher rate (2 Meters/Minute) than a PAL or SECAM machine (1.42 Meters/Minute). In other words, the NTSC VCR runs slightly faster than a PAL or SECAM VCR and consequently the video tape gets used that much quicker.

This chart compares the recording times of each tape in NTSC, PAL and SECAM:

Recording times of each tape in NTSC, PAL, SECAM
(Time in Minutes)
NTSC Record/Playback
(Time in Minutes)
E-30 45 30 22
E-60 88 60 44
E-90 130 90 65
E-120 173 120 86
E-180 258 180 129
E-240 346 240 173
T-20 44 28 20
T-30 64 42 30
T-45 94 63 45
T-60 125 84 60
T-90 185 126 90
T-120 246 169 120
T-160 326 225 160

Both NTSC and PAL/SECAM VHS cassettes are physically identical (although the signals recorded on the tape are incompatible.) However, as tape speeds differ between NTSC and PAL/SECAM, the playing time for any given cassette will vary accordingly between the systems.

In order to avoid confusion, manufacturers indicate the playing time in minutes that can be expected for the market the tape is sold in:

  • T-XXX indicates playing time for NTSC or PAL-M in SP speed.
  • E-XXX indicates playing time for PAL or SECAM in SP speed.

It is perfectly possible to record and play back a blank T-XXX tape in a PAL machine or a blank E-XXX tape in an NTSC machine, but the resulting playing time will be different from that indicated. It can easily be derived by multiplying with 3/2 or 2/3, respectively.

For example, a T-120 tape runs for 120 minutes in NTSC-SP, but 180 minutes in PAL-SP. Conversely, an E-300 tape runs for 300 minutes in PAL-SP, but 200 minutes in NTSC-SP.

Common VHS Tape Lengths
Tape Label Tape Length Rec. Time (NTSC) Rec. Time (PAL)
T-120 812 ft (247.5 m) 2hrs 6hrs 2hrs 49mins  ??
T-160 1075 ft (327.7 m) 2hrs 40mins 8hrs  ??  ??
T-180 1210 ft (368.8 m) 3hrs 9hrs  ??  ??
Tape Label Tape Length Rec. Time (PAL) Rec. Time (NTSC)
E-120 173.7 m (570 ft) 2hrs  ?? 1hr 26mins  ??
E-180 259.4 m (851 ft) 3hrs  ?? 2hrs 9mins  ??
E-240 348.1 m (1142 ft) 4hrs  ?? 2hrs 53mins  ??

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