The use of a wet bulb and dry bulb was the only way to measure relative humidity in the not so distant past. [It indirectly measures how rapidly the saturated wick of the wet bulb is able to evaporate water--and dissipate heat from that thermometer--given how much moisture is already in the ambient air.] For the 21st century, if you have a humidity gauge that is rated for the temps required, it would make more sense to just go by RH at a given temp.
I'm glad I found this statement. I'm having a bit with the wet bulb conversion (it apparently looks for barometric pressure as well???). As I have a hygrometer, so as long as the RH is within the proper spec, this is all I need to 'worry' about, insofar as humidity is concerned, correct?? I understand the ramifications if there is not enough humidity in the chamber, particularly while the yellowing phase is going on. But what happens if there is too much? For example, if the chart indicates 95%, and you're running 98%, etc. - is there damage done?
While 'researching' I found this:
The major problems which occur during curing are leaf browning, over colouring, sponge, runback and scorching.
Leaf browning is caused by having humidity levels too high when the temperature is increased at the end of colouring. This causes the leaf to continue to respire until all the sugars are used up, causing a reduction in weight and leaf browning.
Sponge is a term used to describe a leaf which has been too wet when the temperature has been increased at the end of colouring. Spongy leaf is typically yellow brown, thick and poor quality.
Runback is caused by moisture from the stem seeping back in the leaf blade once it has been dried. Runback occurs when the kiln is allowed to cool down during the lamina or stem drying stage.
Scorching is caused by an increase in temperature during the final drying stage above 70C. Scorching causes the leaf to become 'cherry red' in colour.
It would seem to indicate that too much humidity/moisture would cause problems once you are starting to raise the temp after yellowing is complete. So, would this mean that you must make sure that leaf moisture and/or humidity levels are within the proper boundaries before you raise the temps for wilting??