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Dew on sensor help please

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#1 Mitchell Duke

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Posted 15 August 2014 - 12:04 AM

I have a peltier modded T3i, and the sensor fogs up in the middle of the night. This started happening when I moved to a more humid Georgia. I tried using dew strips, but it seems as if the camera body opening is too thick and deep for the heat to get to the sensor. I thought about letting the cam shoot all night inside a sealed ziplock bag on the scope to see if that might make the air drier. Any ideas on what I can do to correct this issue?


#2 Jerry Lodriguss

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Posted 15 August 2014 - 01:42 AM

Have you tried a cooler box such as the one made by Gary Honis?




I've used one in humid conditions and you have to put a filter on the front of the 2" adapter and then heat the 2" adapter with an anti-dew strap so the heat gets to the filter.


The desiccant packs in the box absorb any moisture in the box when it is sealed up.


I've never had a problem with the sensor dewing up if you keep everything sealed. 


I've only had a field flattener dew up the first time I used it because I didn't put heaters on it.



#3 Mitchell Duke

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Posted 15 August 2014 - 05:03 AM

I have not tried the cooler box, but this might work. My cooler is the cold finger style, so its inside the cam.

#4 Midnight Dan

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Posted 16 August 2014 - 08:57 AM

Hi Mitchell:


Since you have a cold-finger camera, you don't need a cold box.  Putting a box around the camera with desiccant in it won't help either.  The desiccant will dry the air in the box, but the sensor is in the camera aiming out a tube which is exposed to the night air.  


Putting a clear filter in front of the camera should do the trick.  It will isolate the air in the camera from the outside air.  You can then put a dew strap around the part where the filter is and that will keep the filter free of dew.



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