5D2 weather resistant gave way

[Octarine]

How many % actually the humidity should be in the dry cabinet? I am not sure also

The camera manual will tell you. Here in forum the recommendation goes about 45% maximum. There is no minimum setting, the myth about dry air damaging camera equipment has been busted.
There is no point being obsessed with 45% or 40% when the hygrometer is not accurate. So get a calibrated one or do the salt test to know how far your current hygrometer is off.

 

[raydio]

The camera manual will tell you. Here in forum the recommendation goes about 45% maximum. There is no minimum setting, the myth about dry air damaging camera equipment has been busted.
There is no point being obsessed with 45% or 40% when the hygrometer is not accurate. So get a calibrated one or do the salt test to know how far your current hygrometer is off.

Agreed. The optimal hydration setting should be around 45% for any electronics including camera gear.

 

[Barrios]

Between 40%RH and 50%RH should be good.

 

[Octarine]

Between 40%RH and 50%RH should be good.

Better if you know that the reading is accurate

 

[raydio]

...do the salt test to know how far your current hygrometer is off.

What is the salt test?

 

[Octarine]

What is the salt test?

It's described here in the forum, but here a simple external link with pics:
http://www.wikihow.com/Test-a-Hygrometer

 

[Barrios]

I calibrate all my hygrometers with my Rotronic Hygropalm 21. Used to do salt test but not anymore as I found the test only shows accuracy at 75%RH. The lower it gets, the more inaccurate the hygrometer will be.

http://www.rotronic.com/hygropalm21-hp21.html

 

[Henessy]

I calibrate all my hygrometers with my Rotronic Hygropalm 21. Used to do salt test but not anymore as I found the test only shows accuracy at 75%RH. The lower it gets, the more inaccurate the hygrometer will be.

http://www.rotronic.com/hygropalm21-hp21.html

Mind sharing where and how much did you buy it for? Thanks

 

[Barrios]

Mind sharing where and how much did you buy it for? Thanks

Rotronic HP 21 costs over S$500 for the handset itself. Bought from Supertron Sensing Pte Ltd (same address as Rotronic S.E.A Pte Ltd).

 

[Octarine]

I calibrate all my hygrometers with my Rotronic Hygropalm 21. Used to do salt test but not anymore as I found the test only shows accuracy at 75%RH. The lower it gets, the more inaccurate the hygrometer will be.
http://www.rotronic.com/hygropalm21-hp21.html

What is the accuracy of the device at the average temperature of Singapore, let's say 30 degrees Celsius? The data sheet gives the accuracy only for 23C. So above and below there will be deviations.
The salt test can also be done using other substances, two of them mentioned in the article I have linked fall into the range of recommended RH. Imho, much cheaper and accurate enough for the purposes of storing lenses.

 

[Barrios]

If u read the data sheet properly, it is factory calibrated to 23C +/- 5C and at 10, 35 and 80RH. Accuracy is under 1RH. It allows multipoint calibration here in Singapore with certification. Yes, it is expensive. Not for hobbyists.

 

[Octarine]

If u read the data sheet properly, it is factory calibrated to 23C +/- 5C and at 10, 35 and 80RH. Accuracy is under 1RH. It allows multipoint calibration here in Singapore with certification. Yes, it is expensive. Not for hobbyists.

I did read the sheet, that's why I ask. In other words, if one wants to get it calibrated for 30C then another, likely costly calibration is required.

 

[fatigue]

I don't think the low humidity setting caused the corrosion. In fact, semiconductor components are stored in a dry cabinet set at around 20% RH.
The reason why we cant use the same RH setting for our cameras and lenses is because too dry environment may cause the grease to dry up faster and rubber parts crack easily.
If we really want to protect the boards from corrosion, conformal coating is a good option.