PART 7: TAPES

At the heart of the recorder is a rapidly rotating drum, set at an angle, with the recording heads mounted on it. The tape is wrapped around the drum as it is loaded into the recorder. As the tape passes across the drum, the heads convert the electronic video signal from the camera into magnetic pulses and 'write' the signal onto the tape.

DV OR DVCAM

This camera will record in DV or DVCAM mode. In DVCAM mode the camera spools the tape at a faster speed. So, a 60-minute miniDV tape will record 60 mins in DV mode, but only 40 mins of material in DVCAM mode.

As DVCAM gives a shorter recording time compared to DV mode, why bother? DVCAM is more robust, reliable, gives improved error correction and, on the PD 150 and PD 170 it also allows you to have full control over timecode settings..

I advise using DVCAM whenever possible, because I beleive you should always record in the best quality available.

To select between DV or DVCAM mode you have to enter the MENU...

Switch the camera on
Press the MENU button
Turn the SEL/PUSH EXEC dial until the CASSETTE icon is highlighted
Push the SEL/PUSH EXEC dial in to select the CASSETTE sub menu
Turn the SEL/PUSH EXEC dial until the words REC MODE is highlighted
Push the SEL/PUSH EXEC dial in to select the REC MODE options
choose either DVCAM or DV SP mode on
Push the SEL/PUSH EXEC dial in to select the mode options
Turn the dial to the return option to get out of the menu options

Back to the top.

CHIPPED TAPES

This camera uses a small format cassette. Sony recommends you use the expensive tapes which have memory chips embedded into them. You will need these chipped tapes if you want to add a title, superimpose a title, make title searches or electronically label the cassette. They also allow you to use the END SEARCH function even if you remove the tape and put it back into the camera at a later date.

However, if you're not interested in any of those functions then save your money.

MIXING MANUFACTURERS

Loitering round the various camera forums, one important thing I've learn't about DV tapes is not to mix your manufacturers. Different tape manufacturers use different tape lubricants. By swapping and changing tapes, residues start to mix and stick to your record heads - the result is dropout.

This is important because you won't see the dropout until you review your tapes and by then it may be too late to redo the shot. Remember this is advice from other users not from the manufacturers (who have a vested interest in your brand loyalty).

This image shows a good example of dropout on a re-used tape. The fist image has not been completely recorded over by the second image and you get this ventian blind look. We used a cleaning tape to remove any gunk clogging the record heads to fix this problem.

DON'T LEAVE TAPES:

in the sun, on radiators or near car windows on hot days
in a cold place then move them somewhere warm as moisture will condense on the tape
near a magnetic field (e.g. hi-fi speakers and electric motors)
near mobile phones. If the phone receives a call it can affect the pictures on your tape
where they'll get wet
where they'll get dusty or dirty
in the player for long periods of time

HINTS AND TIPS

Ideally you should record around 1minute of bars and 1KHz tone at the start of the tape. (see reasons below)
Don't try to flip the cassette over to record on both sides - it won't. Plus, you'll damage the tape transport mechanism.
Make sure you have plenty of tapes with you at all times.
Don't be tempted to touch the tape, the natural oils on your fingers will damage it.
Label each tape with the date, story name and the camerawoman/man's name - a simple description of what you've shot on the box may save time later in the edit suite.
As soon as the tape is taken out of the machine, engage the protection tab to prevent someone accidentally recording over your story.

Back to the top.

PUTTING COLOUR BARS ONTO THE TAPE

It is a good idea to record about a minute's worth of bars (and tone - if you have it) at the start of each tape.

I was taught to always record about 2 minutes of colour bars and 1Khz Tone (PPM 4) at the beginning of my U-matic and then Betacam tape. For three reasons....

1) The first (and last) minute of tape is the most likely to be damaged in the factory - because the ends are "handled" when the tape is attached to the spools. So, by recording something that is not for transmission (ie bars and tone) on those first two minutes you reduce the risk of using damaged tape for your good stuff. To remind you not to record right up to the tape end, Betacams gave you a warning when you were on the last few minutes of tape. Now that was back in 1984 and I hope manufacturing processes have improved by now. So, maybe 30sec - 1minute of bars (and tone) would be enough.

2) This seems to be a bit of a dying art now. But, the bars and tone were used to line up the edit suite/circuit/OB truck which were relaying and receiving your pictures and audio. It is always best to line up using a known signal (such as bars and tone). Someone somewhere - probably a bunch of engineers on a jolly at SMPTE HQ - decided what colours the bars should be and how big the signal for each of them should be too (look at them on an oscilloscope and you can see their ordered beauty - truly the work of an engineer). Then all the engineers employed by the broadcasters (i.e. the same ones at SMPTE HQ) agreed with their decision. Which means that if I record them at the correct level and they appear on the NLE at that level - then I know I'm not adding or subtracting anything from my original pictures. Of course, you should line up your monitors too. So, in theory all the effort you put into shooting that moody scene still comes over as moody on my TV at home - not washed out or too dark to see what is going on. I say 'in theory' because few us watch our TVs in a perfect viewing environment and TV sets have their own colour cast anyway (but, that's another story).

3) Bars and tone can be useful in identifying some camera faults. I'm not an engineer, but those who are tell me they can.

OK, enough of the WHY, here's how...

Switch the camera on
Press the MENU button
Turn the SEL/PUSH EXEC dial until the ETC icon is highlighted
Push the SEL/PUSH EXEC dial in to select the ETC sub menu
Turn the SEL/PUSH EXEC dial until the words COLOUR BAR are highlighted
Push the SEL/PUSH EXEC dial in to select the COLOUR BAR options
Choose COLOUR BAR on
Push the SEL/PUSH EXEC dial in to select the COLOUR BAR options - you should now see the colour bars in the viewfinder/LCD screen.
Turn the dial to the return option to get out of the menu options
Record a minute's worth of bars
Turn the bars OFF and start normal shooting.

Back to the top.

Move on to...: Part 8: TIME CODE
Or back to...: Part 6: BATTERIES

Christina Fox