Leak Sentinel Leak Detector

[diverdoug1]

This is a forum to get ideas and help if you are happy with your housing fogging and just wanted to have a rant than so be it

---------- Post added April 4th, 2014 at 08:17 AM ----------

Just want to add a little bit of other info

vacuum may actually increase the humidity in the housing
Example: housing with 100 grams of air 2 grams of moisture in the air 0.5 grams of moisture trapped in the camera. Moisture/Air 2.5/100=2.5%

Create vacuum -200 mbar 80 grams of air 1.6 grams of moisture in the air 0.5 grams of moisture trapped in the camera. Moisture/Air 2.1/80=2.625%

I would say that is not possible to draw any conclusions on the effect of vacuum as the amount of moisture in the camera is unknown but certainly not zero so things could actually get worse with more vacuum

No rant here, just disputing your clain that aluminum housings can't form condensate on their ports, which is total horse flop.

As far as vacuum increasing humidity, that is also horse flop

Producing a vacuum will decrease the partial pressure of water vapor in the housing , which decreases the relative humidity in the housing once the temperature equilibrates

This will decrease the dew point . At 30°C and 75% relative humidity, if you pump you housing down 10 inches Hg, you will decrese the relative humidity to 67.5% and the dew point (temp for the housing surface to form condensate) will decrease from 25°C to 18°C

You make the mistake of assuming that the water vapor is left behing in the housing as you produce the vacuum, which is incorrect according to Dalton's law, As overal pressure decreases, the vapor oressure of water, and total amount of water vapor in the housing decreases. You don't just suck out dry air as you produce the vacuum! :rofl:



I still want to know where to get one of those magic housings though.

 

[Interceptor121]

Except there was already trapped moisture on the housing you didn't suck
The camera is a moisture trap but not as good as a desiccant
Vacuum may or not improve matters depends
Also shooting style changes things so you and I could go with the same equipment and it could be still shooting whilst you are taking pictures of fog and viceversa
Maybe I should come and take pictures for you lol

 

[diverdoug1]

Except there was already trapped moisture on the housing you didn't suck
The camera is a moisture trap but not as good as a desiccant
Vacuum may or not improve matters depends
Also shooting style changes things so you and I could go with the same equipment and it could be still shooting whilst you are taking pictures of fog and viceversa
Maybe I should come and take pictures for you lol

No thanks, I have seen some of your pictures

 

[Interceptor121]

Let me have a look at yours if you have any without fog of course

 

[diverdoug1]

If only I had one of your magic housings!

 

[Interceptor121]

You have it already but seems with you is not working

 

[diverdoug1]

But I thought you said

So a personal with normal IQ would read condensation in an aluminum housing happens on the metal and not on the port.

So how could stupid little old me be ever getting condensation on my non-magical port?

 

[Interceptor121]

That I do not know you came here from somewhere else wanting to make a point but as you don't want to share anything about the way you get into that situation and all you seem to be interested is to pinpoint parts of my post without telling anything useful about your specific problems I am afraid there is nothing that can be done to help so I leave it to you to try and figure out farewell

 

[diverdoug1]

I don't need to figure out anything, I am just illucidating the point that
1. An aluminum housing can, in fact, get condensation on the port.
2. Pulling a vacuum on the housing will decrease Relative humidity in the housing, thereby decreasing the temperature at which condensation will form.
These are facts which you don't seem to grasp, which is OK as long as you don't keep trying to spread your misunderstandings on these subjects.

 

[Interceptor121]

If there was only air in the housing you would be right. But there is also a camera in there that acts as a moisture trap. Once the camera heats up the moisture is released and humidity changes. Depending on how much it changes the vacuum may or not make things better. Any housing can get condensation on the port if it's hot and you throw is in a bucket of ice however usually temperature changes are gradual and condensation forms first on the surfaces that are colder. In a plastic housing this tends to be the port as this is is a better conductor in an aluminium housing it is the metal that conducts more than the port. This is as far as I have experienced myself. On top of that the activity you do with the camera also has some influence. Any camera has moisture inside if you put a camera in a sealed plastic bag and you heat it up and then You cool it you see moisture on the bag that you could not see before. What's is exactly that you disagree with am not clear