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July 23rd, 2011, 03:20 PM | #1 |
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Join Date: Aug 2009
Location: Chicago, IL
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Minimum Time to Warm Up to Hot & Humid Weather
I have my cameras sitting in my studio at 72 degrees F (22 C for those across the pond) and will be recording an event outdoors tomorrow which should be 90 F (32 C) and extremely humid. The problem I have is that I cannot get the cameras until 15 minutes before I need to be at the event. However, I can have my assistant arrive earlier and put the cameras in his car to begin warming up, but he will be on a tight schedule as well. So, I am wondering what has worked for others.
On a side note, this last Wednesday night, I had to take an EX3 to shoot an interview (about the extreme heat) and I had the camera in my car for only 10 minutes with it still being 89 F at 9:30pm. The camera instantly became wet with condensation and the lens fogged up which I wiped down as good as possible prior to recording (which only lasted 5 minutes and then back to the AC in my car). So far, the camera is still working normally, but this was a bad decision, correct? Thanks |
July 23rd, 2011, 03:42 PM | #2 |
Regular Crew
Join Date: Mar 2008
Location: Palm Harbor, Florida
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Re: Minimum Time to Warm Up to Hot & Humid Weather
Here in Florida, heat and humidity are big problems when coming out from a nice cool air conditioned office. I found a small 12 volt hair dryer at a camping store. I use it in my truck if the lens fogs. Back in the days of tape, I used it to carefully warm up the tape heads. It usually took only a few mimutes.
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July 23rd, 2011, 03:53 PM | #3 |
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Re: Minimum Time to Warm Up to Hot & Humid Weather
Most important number is the dew point. 72 is pretty cool so likely a few degrees below the DP. If you can get it warmed up to above that number you should be good.
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July 23rd, 2011, 04:11 PM | #4 |
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Re: Minimum Time to Warm Up to Hot & Humid Weather
The typical procedure for the cold-to-hot routine is to seal the camera in a large airtight bag until it has reached a temperature closer to that of the location. Thus the humid air isn't inside the bag and doesn't condense on or inside the camera (perhaps on the outside of the bag, but not inside) when the camera changes environments. 15 minutes sounds about right for typical warm-up, Don't keep the camera in its camera case during this, since the case will tend to insulate and thus make the temperature adjustment take longer.
Obviously the higher the humidity and the larger the temperature differential, the worse the problem. |
July 23rd, 2011, 07:17 PM | #5 |
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Location: Houston, TX
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Re: Minimum Time to Warm Up to Hot & Humid Weather
One quick fix:
If you are in the field and do not have a hair dryer available, use your car heater. Leave the A/C engaged, but turn it to the warmest setting. It will be miserably uncomfortable to you, but it will save you if you cannot repeat or delay a shot. It has worked for me several times over the years.
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Bill Rankin |
July 23rd, 2011, 09:40 PM | #6 |
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Re: Minimum Time to Warm Up to Hot & Humid Weather
Surprisingly, (because we never have to suffer the sort of warmth and humidity you enjoy in FLA) this problem is encountered in the UK though at different temperatures/humidities.
A couple of years back I was recording a wedding on 31st December. Unusually, because in reality our weather is almost boringly moderate, we had snow and freezing temperatures. After the church ceremony, the couple were going outside for some group shots and then immediately into a pub conveniently located at the church gate. We were shooting with Z1s in those days and as soon as we entered the snug warmth of the pub, replete with open fire in an Inglenook fireplace, the front element misted. Although we waited a few minutes before shooting the general "mingling" activity, the arrival of the bride and groom was recorded as if through a very heavy diffuser. For once, being an event recording saved us because our explanation was that we recorded what everyone wearing spectacles saw at the same moment! Fortunately only the front element was affected and on our own evidence I'd agree that 15 minutes seems adequate for any such condensation to clear. I guess the more extreme situation would be condensation on inner surfaces when some of the more radical but ingenious solutions mentioned already would be useful. |
July 25th, 2011, 08:30 AM | #7 |
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Location: Bracknell, Berkshire, UK
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Re: Minimum Time to Warm Up to Hot & Humid Weather
Just remember that the camera has a metal body. If there is condensation on or in the lens, there is also likely to be condensation inside the camera body. If that condensation is deep inside the camera body then it will take a prolonged period of warm dry conditions to get it truly dry. There have been several reports of moisture damaged circuit boards inside solid state cameras in recent years, some resulting in the total loss of the camera.
With tape camera's we always knew about this because the cameras incorporated a "dew" sensor on the head drum to prevent tape damage. There is no such sensor in the EX cameras, so no warning of potential disaster. NEVER Pack a camera in a watertight case or sealed bag without including silica gel or some other desiccant to absorb moisture. Using a sealed bag to get the camera from cold to hot will prevent condensation and is an acceptable practice (IMHO) provided you do allow sufficient time for the camera to warm up fully before opening the bag.
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Alister Chapman, Film-Maker/Stormchaser http://www.xdcam-user.com/alisters-blog/ My XDCAM site and blog. http://www.hurricane-rig.com |
July 25th, 2011, 10:25 AM | #8 |
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Re: Minimum Time to Warm Up to Hot & Humid Weather
Thanks guys.
It was a moot point yesterday thanks to the severe storms yesterday morning, which caused the electronic key card system to malfunction and not let me in. (I will get keys to prevent this problem from occurring again) About a year ago, I believe it was you, Alister who said that sealed, air tight cases were bad for storing cameras due to moisture. Because of that, I bought a Kata One-Man-Band case which holds my EX1, EX3 and XR500V and all accessories. Now, my hard & airtight Storm case (designed for an EX1) holds my Zacuto gear and nanoFlash but the case is always open. My Kata OMB case is not the most rugged and needs to be replaced due to a broken trolly and a design flaw in the trolly where the bag rubs against the wheels which has created a hole on the corner of the bag. For a $400 bag/case, its durability is very disappointing, but everything else about it is great. I think that a good way to get around the design flaw is to put duct tape (or maybe gaffer's tape) on the corners and then be very careful with the trolly's handle when there is a lot of weight in the bag so the handle doesn't break like mine. |
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