Humidity/Condensation recording with TRV510

[Sillyname]

A guy next to me, with a JVC S-VHSC camera was getting a constant condensation alert on his LCD, whilst I was happily recording away on a night so humid you could flap your arms fast enough to raise your feet off the ground.

Do the camera companies take into consideration where their cameras are being shipped to? I seldom wonder if the reason why the white balance is "automatic" on my camera, is because it was just set to the light/color specs of the inside of some flourescent-bathed manufacturing warehouse in Japan...

Or maybe they figured that more people are staying indoors these days, so they set the camera accordingly...

I'm surprised with the low color smear of my cam, though. (Believe it or not!) I went to the Art Car Museum in Houston and filmed some cars that were decked in everything from Mardi Gras beads to Easter motifs. In other words there was lots of chance for color smear as almost every frame consisted of every color in the rainbow, including a few that I can almost bet they didn't have around for testing, like Pink Foil and Day-Glow Orange.

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Deep is not the root word of depression.

[Dr Mordrid]

I don't think a lot of companes take into account where a cam is going at all. Otherwise all they *might* consider better case designs

As for poor auto white balance, this is appears to be a common problem. Just another in a myriad of attempts to make cams usable by idiots. I don't mind it being there as a default mode, I just wish they would put at least a minimal manual mode in all of 'em for those who need it.

Dr. Mordrid

[Sillyname]

White Balance is the one thing that should remain analog...

Oh, hey Doc? Look at this: http://www.nucoretech.com

Go to the Products area and read about the technology that goes into these puppies!

[Grigory]

I have an opposite case with color balance of 110: it is good outdoors, but not perfect indoors. So, these setting are probably vary from unit to unit.

100% humidity in summer and down to -10 C last winter were not a problem for my D8 camcorder . I did not try lower temperatures. However I was shooting with raindrops falling on cam many times without any humidity warning.
One possible reason is that the mechanism keeps higher temperature and this keeps humidity level inside the case lower than outside (remember faster head rotation for D8).

Grigory

[Patrick]

Grigory, are you suggesting that an added benefit of D8 camcorders is their ability to keep Muscovites warm on cold Russian winter nights?

[Sillyname]

If you carefully clench it between your knees.

[mynx]

On sony cams the dew sensor is on the capstan motor. In jvc it is mounted to a plate near the audio/control head. The heat from the motor will keep the sensor warmer. The sensors don't measure humidity, they sense dew. Dew results from a difference in temperature.
There is no consideration about were a unit is going aside for country specific issues.
I wish white balance could be controlled. It is the hardest alignment to do. The camcorder reads the light and decides if its inside or outside.
The faster heads speed doesn't result in any increase in heat but the IC's do. If the camcorders ic's had dropped to -10c you wouldn't be filming. Most ic's fail at 0c. The CCD's also fail at these temperatures.
By the way, water in the camcorder won't activate the dew sensor but will corrode the non-repairable boards. Be warned.

[Patrick]

mynx, I understand that you are a Sony technician. Do you have any comment on the "hacks" that can be done to Sony camcorders through their LANC connectors? For example, is there any reason why someone would NOT want to enable manual white balance on their Digital8 camcorder?

[Brian Ellis]

Hi, guys

This is a subject where I have a little more than a passing knowledge. It is necessary to differentiate between water, humidity and dew. Water (Grigory's rain drops) will have no effect on the functioning of a camera, provided it is kept outside the housing (or off the lens!). Humidity, per se, is generally totally innocuous to the operation of a camera and I have often filmed in tropical rain forests without problems. However, there is a longer term risk with high humidities and temperatures. The printed circuit substrates are slightly hygroscopic and consumer/prosumer goods are nowadays surface-mount soldered using "no-clean" pastes which do leave ionic residues. The combination can lead to long term ionic or galvanic currents, resulting in corrsion, loss of surface insulation resistance and other nasty and irreparable damage. The risk may be reduced somewhat by ensuring that the battery is connected only when actually filming, under such conditions. Dew is the real bugbear. It can cause three problems. The most severe is that condensation causes the tape transport to stick and if you insist , you will cause damage to the mechanisms. This is why the sensors are usually in or around the tape drive. The next is that condensation on the electronics may also cause similar problems as described above plus the formation of dendrites (these are microscopic metallic whiskers which can short-circuit neighbouring conductors on a printed circuit). The last one is the obvious one of internal lens surfaces steaming up. The most usual conditions for dew to form is when removing the camera from a cool environment to a warm, humid one. The worst cases I've experienced have been when getting out of an air-conned car, after a long trip, straight into the jungle (the human frame doesn't like the contrast too much, either ). If something like this happens, the only thing to do is to be patient. I leave the camera open (tape and battery removed) for about half an hour and then everything is OK. However, when in the tropics, I try to avoid the problem by using an ice-cooler pack and keeping it in warm water (about 40-45°C) for an hour before the trip starts. I put it in the camera case. It stays warm for quite a time, because the padding in the case is a reasonable thermal insulation. This keeps the camera at an operable temperature, above the dew point, for at least 2 - 3 hours, even in a taxi where the air-con is always on at max.

Sorry for the techie monologue, but I am professionally involved in the reliability of electronics under adverse conditions.

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Brian (the terrible)

[IvanP]

Grigory,

You've got a factory enabled TRV110E. Aren't you? That means you don't have a WB manual control enabled. I've found it's worth of the effort to enable it. You'll find a new menu in manual camera control with four otions: Auto (already set in your cam), Hold (remembers the last settings), indoor and outdoor (presets).

I'm never using an AE programs. Often I'm using a manual exposure mode. I've also enabled show clone/gain which shows me the actual values while recording.

I've found the best settings for indoor low light (40-60W), in normal auto mode it produces a "blue" color noise, everything has an yellow/brown tone, max clone, max gain 18dB):

Best settings for TRV110E:
1, Set WB to indoor (yelow/brown tone disapears, partially "blue" noise too)
2, Use manual exposure.
3, Turn off the image stabilisation. It enables you to drop gain more (to 6, 9 or 12dB, depends on you).

Result: No "Blue" noise, colours are closer to reality.

Ivan.

[This message has been edited by IvanP (edited 26 September 2000).]

[Patrick]

Ivan, two questions:

1) When manual white balance is enabled by using a "hack", do you not have a mode where you can actually set the white balance by pointing at a white object and "memorizing" it? Or is that what you were referring to with the Hold setting?

2) What is it you mean by "clone"? (This might be a translation problem. )

[IvanP]

Hi Patrick,

Unfortunatelly there is no such "learning" mode. Hold means if you're satisfied with actual autoWB and choose hold the WB settings will stay "frozen". Maybe there is a trick how to "tell" it "This is white" in auto mode and "hold" it. I'll try some experiments but I don't know any reasonable procedure or method.

Clone (I was in "direct translation mode" ). The correct expression should be - iris.

[Patrick]

Ivan, by your description of the Hold mode, wouldn't it work the same way as a "learning" mode. Couldn't you just point the camcorder at an all white subject, and then after the AWB does it's thing, put the white balance in the Hold mode?

[mynx]

Patrick: Being an authorized sony servicer I can't perform this. I don't know of any reason for not doing it on your own. Except the possibility of changing the wrong data. As long as you record the original data before you change it, you should be fine.
Is there a site the details what locations to change for various models? I own an HI8 and would like to activate it in mine.
Brian Ellis: The battery should always be removed when not taping. Camcorders have what is called a dark current, they will drain a battery that is left attached.

[Patrick]

mynx, there's info and several links mentioned in these three recent threads.

http://forums.murc.ws/ubb/Forum2/HTML/004881.html

http://forums.murc.ws/ubb/Forum2/HTML/004882.html

http://forums.murc.ws/ubb/Forum2/HTML/004886.html