VIDEO CAMERA 2000

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ASK RICK JANUARY 2000

 

PANASONIC OFF COLOUR

I found the article in the October issue of Video Camera on the topic of additional lighting very interesting. However, I was hoping you would give advice on how to avoid some of the problems of filming indoors, especially as the editorial correctly assumed that most camcorder users press 'record' and hope for the best.

 

Recently, I have purchased a Panasonic DS33 camcorder and the only problems I have experienced regarding picture quality was filming indoors. I have two examples. I was recording in a workshop with very good natural daylight. The first sequence was excellent for colour. The camera was then set to pause and pointing down to the floor whilst waiting for the next shot. When the camera was then brought up to the eye, the scene in the viewfinder was very grey and most of the colour had gone as I pressed record. Needless to say, when shown on the TV the two scenes looked very different.

 

I wrote to Panasonic, as I thought I had a malfunction, but the replay suggested the problem was caused by pointing the camera at the floor and that it would take the camera about seven seconds to readjust to fresh lighting. Try as I will I cannot reproduce the problem.

 

In another sequence, I was recording in a very small, brightly lit room with one window and recessed tungsten ceiling lights. Depending on where the camera was pointing, some shots were good for colour while others were blue and pale. Any advice on how to avoid these problems, without additional lighting, would be appreciated.

G. B. Turner,

Norton-in-the-Moors,

Stoke On Trent

 

The root cause of your problem is not the type or amount of light – it sounds as though there's more than enough in both cases – but the way you are using your camcorder's white balance system. Panasonic camcorders have a better than average reputation for colour accuracy in a wide range of lighting conditions, but even the best white balance systems can make mistakes, if they're not set up properly. Nevertheless, the problem in your first scene rests squarely with you since you say that the image in the viewfinder showed colour faults, yet you went ahead and pressed the record button anyway! In my experience Panasonic camcorders respond to lighting changes in much less than 7 seconds but there's no doubt that if the machine was on full auto it would have taken a few seconds to compensate for such a big change in scene lighting. If there were colour errors lasting for the whole scene – i.e. longer than a few seconds – and since you can't reproduce the error, it's possible that the WB system was on a manual setting. Have another look at the instructions and get into the habit of setting white balance manually prior to each shot, it only takes a couple of seconds.

 

The colour faults in the second scene are characteristic of the way some camcorders deal with mixed lighting, when one type of light (almost certainly the tungsten ceiling lights) predominates or shines onto the front of the camera. The solution in this case to take care with the framing of the shot, to avoid single points of bright light, and to aim for a more diffuse lighting, try using white boards or reflectors out of shot.

 

SECRET CODE

My camcorder is a Sony DCR-PC7. I have recently brought a VideoTech VEC-501 Multi-Scene storyboard editor. To get the full benefit of the editor I need to be able to timecode my camcorder tape and connect to the editor's Control L socket. Although Video Camera Buyer's Guide chart shows my camcorder as having a timecode facility I am unable to find an 'in' socket on the machine, other than the power socket, and I can find no instructions in the user manual on how to put a timecode on the tape.

 

I am grateful for the Jargon Buster section of your magazine but I am wondering whether the meaning of the term Timecode has changed since my machine was introduced. Have I missed something about the PC7 or have I been sold a pup?

 

I know the VCC-501 can write a timecode but unless I can link up the camera to the editor. It will mean adding an extra generation to the editing process, editing from a copy tape. Incidentally, a friend who also has a VEC-501 and a Sony Hi8 camcorder has been able to set up a timecode editing system quite easily, although we are both in our 70's, and struggle a bit with the terminology.

Frank Waudby,

Bayston Hill,

Shrewsbury

 

The topic of timecoding is fraught with difficulties at the best of times, but it becomes a veritable minefield when digital camcorders are brought into the equation. The first thing to say is that all DV recordings are timecoded by default. The digital information that makes up each frame of a recording has a unique address that is used by digital editing systems and PCs. Some digital camcorders – notably the Digital 8 models from Sony – also record a modified version of the RCTC code on the tape. Mini DV machines with Control L terminals can be controlled by some (though not all) edit controllers, but will usually default to reading the standard hours/minutes/seconds time readout. It's been a while since we last looked at the PC7 (over 3 years in fact). However, as far as I can recall the only timecode facility on this machine was the format standard digital data address, accessible when the machine is connected using a FireWire connection to a PC. You should still be able to use your edit controller with the PC7 but edits will not be as accurate as timecode, typically cuts will be to within +/- half a second, though this is usually sufficient for most home movies.  

 

SPECKULATION

I wonder if you can come up with a solution to a problem that I have during editing. The fault is a series of black speckles or flecks that appear in the upper half of the image on screen and are also copied to tape during recording and capture to hard drive. The editor is a Pinnacle Studio 400, which I am basically delighted with, however, when using the Smart Cable 006; the black marks mentioned spoil my work. My camcorder, used for this purpose, is a Sony TR2000, I have two of these and both give the same result. The VCR I am recording to is a Panasonic NV-HS950. The problem doesn't occur when using the 003 Smart Cable or if I disconnect the LANC jack from the camcorder and drive it using its own remote control. Using the 003 cable is not an option as this will not drive my Panasonic VCR. I have two 006 cables and both produce the same results.

 

If the PC is switched on and Studio 400 initialised but not used to control the camcorder the black marks are not present, even with the LANC plug connected to the camcorder. However, as soon as the program's VCR or camcorder controls are used the black marks appear and remain until the PC is shut down.

Harry Moth,

Eastleigh,

Hants

 

Thank you for the demo tape which, shows the marks very clearly. I have to confess it's not something I've come across before but I have little doubt that it is being generated by the PC and fed back to the camcorder by the LANC cable. It would have been helpful to know a bit more about your PC but the size, position and frequency of the lines suggest that it is probably originating from within the Studio 400 and its associated software, rather than other open or running applications on the computer. You might be able to confirm this by pressing Ctrl-Alt-Delete and shutting down other programs one by one and see if that makes a difference. I don't have any definite answers but I do have a couple of suggestions, on the assumption that you have already exchanged the Studio 400 and re-installed the software. The first is to reposition the board, or swap the other boards around inside the PC, making sure that the Studio board is as far away from everything as possible. Secondly check the cabling and ensure that power leads and ribbons are well away from the Studio board. The only other thing I can suggest is to try your Studio 400 in another PC; if the speckles disappear then there has to be something unusual about your computer.   

 

BEATING THE BLUES

I have a Sony TRV310 Digital 8 camcorder. Generally I and quite pleased with it, especially the powerful optical zoom, however, there appears to be a problem with the white balance as I am suffering from a definite case of the blues! I brought the camcorder in the UK in July and after testing it everything seemed fine. Packing it away (with sachets of silica gel) I took it out to Darwin in Australia in September and I will be travelling around for the next few months. Trying it out around the tropical garden of my motel I soon noticed that when using the telephoto lens, blacks, browns and greys had a bluish tinge. Even without the telephoto I occasionally had a problem, e.g. a white wall on one occasion but slightly blue on another. When I video'd a black and white bird (with zoom) on green grass it turned out dark blue and white on green grass and I knew something was wrong! Yet another bird, white with black wingtips in a tree came out okay… Other colours are not 100% accurate but still fairly good.

 

I have tried every combination of controls on the camcorder that I can think of but the only thing that makes a slight difference is contrast – there is no manual white balance.

 

I am a naturalist and interested in wildlife so I need to use the telephoto lenses. What I would like to know is is this likely to be a fault on the camcorder and could it be caused by the humid conditions in Darwin? If so what can I do? I am beginning now to wish that I had brought the Sony TRV510, which has a manual white balance control.

John Hackney

Deal,

Kent

 

If by some chance you come across this issue of Video Camera on your travels I trust you are not making judgements about the colour balance of your recordings based on what you see on the 510's LCD viewing screen. Even though LCD screens have improved enormously in the past couple of years they are simply not reliable when it comes to assessing colour accuracy. You should get a better idea of by connecting your camcorder up to a TV, though even then you can't be sure that an unknown motel room TV is properly set up; you will just have to wait until you get home for the final answer. It is just possible that your machine suffered some damage in transit but I would have expected any faults to be much more pronounced. I think it unlikely that the problem is caused by high humidity since these machines are designed to work in a wide range of temperatures and conditions.

 

However, assuming that the errors that you are seeing are real and being recorded on the tape then that would indicate that the camcorder's auto white balance system struggling. I imagine the light is a good deal brighter and colours more intense out there and in such conditions WB systems can over compensate or make mistakes. The simplest solution is to fit a neutral density filter (ND4 is most suitable) to your machine, which will reduce the amount of light entering the lens, without affecting the colour tones, and hopefully help the machine's WB system to make more accurate assessment.

 

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ã R. Maybury 1999 1411

 

 

 

 


 

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