Humidity and digital phgraphy

<p>I live in a place where the air is humid most of the year. Stepping outdoors from an airconditioned building the equipment fogs up instantly: but even if I wait for my equipment to adjust to the outdoor temperature, the humidity fogs the sensor and every shot is foggy. What can be done? I can use film for backup, since there is no issue with film and humidity but my digital equipment doesn't cope.</p>

<p>Depends on the camera and factors I haven't been able to figure out. So far my most reliable digital camera in any weather is a nearly decade-old Olympus P&S. It keeps working even when I have to frequently wipe the condensation off the lens (or filter - I usually use a protective filter when weather or humidity is a problem).</p>

<p>My Nikon dSLR (D2H) has failed once after exposure to weather that ranged from heavy fog to light misting rain over the course of several hours. Other than that one incident it's worked well even when I've had to wipe the lens and viewfinder every few minutes. Even in conditions you've described - going from a cold air conditioned building to sweltering humid heat - the sensor itself never fogged up. Ditto the reverse - going from very cold outdoors to warm buildings.</p>

<p>I'd suspect that if you're in conditions severe enough to fog the sensor, you'd have problems with film too. Occasionally heavy condensation can cause film emulsion to soften and swell. At a minimum this can cause scratches and scuffs with 35mm film and in severe cases can temporarily stiffen or lock up the advance mechanism. Medium format film seems a bit less troublesome since the film doesn't run through a narrow channel covered with a felt-type light trap. But I can't recall ever having been caught in high humidity with my medium format cameras. You'd probably get more experienced answers from dedicated nature photographers who've been through all sorts of weather with film cameras.</p>

<p>Do you keep a good multicoated UV filter on your lens? If so, consider removing it, and putting it close to your body, perhaps in a shirt pocket. Let it get up to 98 degrees. Re-mount the filter right before you step outdoors. That front glass surface will be much warmer, and less likely to draw condensation. <br /><br />When you're having a fogged <em>sensor</em>, is this when you're removing/swapping lenses outside while the camera is still tens of degrees colder than the surrounding humid air? Just don't do that. Keep the lens mounted until things warm up. You won't get <em>that</em> much air circulating into the camera body, if the lens stays put. Are you sure you're not seeing the external viewfinder glass fog over, rather than the sensor?</p>

<p>Is there a safe, secure place where you might store your equipment outside for a few hours prior to shooting--or at least somewhere with the same approximate heat/humidity? Maybe an unairconditioned store room or garage somewhere? </p>

<p>Condensation occurs on colder than the surroundings objects. Period.</p>

<p>So: if you want to avoid condensation on and inside your gear, put your camera etc into a tight ziplock bag inside your air conditioned house, move the "package" outside into the sweltering moist heat for a couple of hours (overnight?), wait a while (hours for the temps to equilibrate) and then remove the bag and shoot happily.</p>

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<p><em>"even if I wait for my equipment to adjust to the outdoor temperature, the humidity fogs the sensor and every shot is foggy. What can be done? "</em></p>

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<p>This is a D90? If so, wait for the temperature to equalize as you've said, then try turning on live view for a duration necessary to clear the fogging.</p>

<p>The theory is that the sensor's self-heating effect will raise its temperature above ambient to negate the problem. </p>

<p>Even film will fog with longer times in AC but it does seem to equalize a bit quicker. I generally haven't seen sensor fogging unless I change a lens before the camera gets warmed up. This allows the hot humid air inside the camera body. My body is weather sealed, so one that is a bit less so might exhibit issues in this regard--although I never saw it happen with an old Rebel XT I used for scouting before I started shooting digital, but I had just one lens and never changed it.</p>

<p>Even having the camera in the car for a prolonged period between stops can cause some fogging if the AC has been running and things are hot and humid outside. Generally it goes away more quickly than when the camera has been inside in AC over night as the camera/lenses don't cool down into their core. If you are driving between locations it is sometimes better to put the camera in the trunk than keep it in the cab with you if you don't want to wait before shooting--or don't run the AC.</p>

<p>I spend 80% of my time in South East Asia where the humidity can be cut with a knife... I also have had many problems with humidity, including losing a camera and several lenses due to mold building up inside the elements and on the sensor. I keep my camera and lenses in a dry safe as much as i can. These can be purchased in any good camera store for a few hundred $ or less and it can save you thousands of dollars. I also avoid air conditioning so the camera and the lenses are generally at the ambient temperature to avoid condensation to take place. Of course if you live in a cold humid climate the problem will be coming indoor from the cold to a warm humid house. Other than letting your camera and equipment adjust to the change in temperature, i would not know what else you can do. Good luck</p>

<p>Thanks for all the replies and suggestions, especially to Michel Latendresse. Your advice was precisely what I was looking for: something from someone who has experienced a similar difficulty. The weather in my town (Miami, Florida) at times renders outdoor photography practically impossible. I've exprienced this often with a variety of equipment from different manufacturers. And as I mentioned in my first post, pre-warming the equipment doesn't solve the problem. It's not the lens that fog up. It's something in the camera: I presume it's the sensor. Thanks again for all the comments. Perhaps, in the future there will be some technology to deal with this issue: at a premium price, no doubt.</p>

<p>Andrew: If the camera truly is warmed up to your outside temps, no water vapor will condense to fog on any surface of it. Just put it in a sealed zip-lock back, and let it come thoroughly up to temperature.</p>

<p>Andrew, I have been taking photographs in tropical countries for quite a few years now and worry endlessly about humidity and take a lot of precautions - so far I have escaped any major problems. I always keep the cameras in their cases for about half an hour when going from one temperature to another, I fill my camera bags with silicone gel bags which I dry out from time to time and I never shoot in rain. I find AC very useful because although it causes temperature problems it also creates a very dry atmosphere and so I try to leave the cameras out in it for a few hours every day.<br>

In jungle camps I stay in where there is no AC there is often a homemade hot box which computers,cameras,printers etc are left to dry out in. This is a crudely made wooden box with a lid and a light bulb in which is left continually on, its not perfect but it does help.<br>

I use Nikon,Canon and nowadays Mamyia so its not a brand thing. The only camera that ever did fail me was an old Pentax film camera in a forest in Malaysia and it was wet wet and it just seized. Other than that as I said I haven't actually experienced any real problems (touch wood!) and the places I go to are a lot more extreme than Miami -are you sure its a problem affecting all cameras? It might easily be some thing you're doing that you haven't realised yet.</p>