My entire editing setup consists of standard VHS VCRs. To add audio and video dub ability, I would like to replace the recorder with an S-VHS editing VCR. Will I be able to edit my standard tapes? Will I need two S-VHS VCRs? Will I have to use S-VHS tapes? Will I be able to play the edited tapes back on my standard VCR?
Johannes B. Backes
Yes, you will be able to edit your standard tapes, an S-VHS deck will record and edit standard VHS video. No, you don’t need two S-VHS machines. A standard VHS desk will work fine as your player, unless you replace your camcorder and start shooting on S-VHS. No, you don’t have to use S-VHS tape in your S-VHS machine, but if you don’t you will not be recording in the higher quality S-VHS format. You will not be able to play S-VHS tapes in your standard machine, (unless your standard machine is new enough to have quasi-S-VHS playback). You will have to make dubs for playback in a standard VHS machine. It is a good idea to edit your master tape on S-VHS, make standard VHS dubs for playback and put the master away in a safe place. When the standard VHS copy gets damaged or worn out (which it eventually will) you can make another copy. Overall, you won’t see much of an improvement in video quality from your record deck upgrade until you also upgrade to a higher resolution format for your source video footage.
I hope you can answer my question about the sampling rate applicable to some high-end digital video cameras. I don’t understand what the sampling rate 4:1:1 means. Is 4:2:2 better than the 4:1:1? Is it something that you can see? Thank you for any information that you can provide!
Richard H. Syx
There are many different sampling rates used to digitize images and they are identified with numbering systems (of which the most common for video is 4:2:2. In Digital Video (DV) the number stands for the luminance (Y) signal and the next two numbers are the color difference signals, red luminance (R-Y) and blue luminance (B-Y). The specific numbers describe how the samples relate to each other. In the 4:2:2 system, for every four samples of the luminance signal (Y) there are two samples each of the color difference signals, (R-Y and B-Y). The 4:2:2 system gives more chrominance bandwidth in relation to luminance than 4:1:1. In the 4:1:1 system chrominance information is sampled at half the rate of the 4:2:2 system (one sample of the color difference signals for every four samples of the luminance signal) making it a more economic method of sampling. The difference can be hard for the untrained eye to see, but there is a loss of chroma (color) depth.
If a digital camcorder, such as the Sony VX-1000, has 500 lines of resolution and an S-VHS camcorder, such as the Panasonic "Super Cam" 800, has 750 lines of resolution, which one has the best picture? I am going to purchase one of these camcorders. The reason I’m considering the S-VHS is because you can digitize your footage and if it’s based on lines of resolution, than 750 lines should show the best picture, right? Also, S-VHS tapes are a lot cheaper than Mini DV tapes.
There are two aspects of horizontal resolution to be aware of. One is the horizontal resolution of the imaging system in your camcorder. The other is the horizontal resolution of the recording system in your camcorder. For example, the DV format is capable of recording 500 lines of resolution. However, the imaging systems (the lens, stabilization system and CCD) of many low-level consumer DV camcorders are not capable of 500 lines. Those camcorders will only record the resolution the imaging system is capable of producing (often between 350 and 450 lines). The S-VHS format records only about 400 lines of resolution. In either case, the quality of the recorded signal is only as strong as the weakest link. Also note that some quality is lost in digitization, which varies with codecs and compression ratios. Probably the only way to settle these variables is in a real test with your editing gear.