A question on dew point/ condensation (geeky post)

[Marrduk24]

 

Thanks to all the wonderful contributions on this forum, I have learnt a ton. 

Just an abbreviated version of what I have learn so far and then an open question. I am simplifying it a bit:

1. RH = actual humidity / maximum humidity that air can hold at that temperature 

2. Maximum humidity that the air can hold goes up as the temperature goes up. Hence at any given RH level, actual water content in the air is higher at higher temperature

3. Dew point/ condensation: probably easier to illustrate with an example - at 65f temperature and 65% rh, dew point is 53f. Which means if surface or air temperature drops below 53, condensation will form on that surface or in air.

Hopefully I got that mostly right 

Question - 

Let’s say the temperature and humidity inside the humidor is 68F & 65% RH - dew point will be 55.7f. There are only two paths to possible condensation

1. I cooled the unit to a temperature lower than 55.7f without reducing the actual humidity in the air. At 55.7f actual humidity in the air will equal the maximum humidity the air can hold and condensation will form - I am unlikely to do this
2. More humid air from external environment gets introduced as you open the humidor and dew point of that air was lower than 68f I.e. the temperature inside the humidor, and that causes condensation inside the humidor. This seems to be the more likely path to condensation

I created a chart to see at what external temperature the air holds enough humidity such that if that air were to be introduced to humidor, which is at 68f, condensation will form inside the humidor. I created based on different levels of external humidity. Here is how I am interpreting this - say external humidity was 60% RH. In that case any external temperature above 82f the air holds enough humidity that if that air were to be introduced to the humidor, which is sitting at 68f, the condensation could occur.

Am I thinking of it the right way?