British Color Experiments - 1950s mystery photos

[ceebee23]

The development of slant azimuth recording made it possible for Beta and VHS to to use much less tape than previously needed.

"Slant azimuth recording" means that the recording heads are not in line with each other but are offset by a small amount ...again apologies if I am a little inaccurate here..but with VHS I think it 6 degrees and beta 7 degrees ..or something similar.

This enabled Beta and VHS to do away with guard bands betweens each head pass over the tape effectively doubling the capacity of the tape.

The main difference between recording speeds is not resolution so much as signal to noise response. Hence LP and EP etc for VHS and BIII on Beta resulted in less saturated colour and noisier images with increased delta gain.

This is also why the improvements in tape were so important and made it possible to introduce the lower speeds. (And also the introduction multi head recorders with the different heads optimised for the different speeds resulting in much better low speed recording).

The introduction of HiFi recording for vcrs is whole 'nuther story since the spec for NTSC Beta enabled the sound to recorded in a "gap" in the signal, whilst with VHS this was not possible and resulted in the so called depth multiplex system with the sound signal recorded under the video signal.

The PAL Betas uses the same system as VHS to record HiFi as the signal spec does not have the "gap" utilised by the NTSC variant. (In fact NTSC Beta introduced HiFi stereo some time before it was available for VHS or for PAL Beta).

Of course the other significant tape development was the new bases which were thinner but capable of handling the stresses imposed in the recorders without stretching.

If you can remember the dim dark ages (ie the early 80s) VCR tapes came in basically one length L500 (two hours as NTSC BII or 2hours 10 minutes for PAL) and L750 (3 hours for BII and 3 hours 15 minutes for PAL Beta), and T120 NTSC or E180 for PAL VHS.

PAL Beta never adopted slower recording speeds.. there was no BIII for PAL Beta.

VHS T120 cassettes gives 2 hours at SP on NTSC but 3 hours on PAL ...this is due to the different frame/line rates. 625x50 does not equal 525x30 ...the heads spin more slowly (1500 as opposed to 1800 rpm) so PAL recorders use less tape.

The T160 (E240) tapes arrived by about 1984 and the L830 by '85. T200 tapes (E300) arrived in the early 90s...but were intially very expensive.