wayno wrote:temperature difference becomes academic when it means you're so hot you're sweating heavily inside the jacket, the gore tex won't have a hope of shifting the mositure.
you're letting moisture out with pit zips as well reducing the amount that needs to move through the gore tex....
you can talk all you want about temp differential. i've walked on cold dry days with a rainshell on and even on the flat with plenty of wind, i built up sweat inside, gore tex can't cope with the sweat generated during prolonged exercise...
That's exactly right. It's only when you stop exercising and generating sweat that it can begin to make any progress on transpiration.
And only if you maintain or increase the temperature differential.
It is important to note the technology was not initially brought about to cater for your needs as the general public.
Space men may generate some sweat through the stress of the functions they perform but they're not really out there to exercise for the sake of exercise.
This highlights the fact that technology is not the answer for everything. It just provides a little assistance.
I make it a point to tell people they probably don't need a breathable jacket. Particularly if the cost is bothering them.
Most of them are not in remote environments doing life threatening things such as explorers or true adventurers.
Opening pit zips will reduce the process of transpiration so dramatically that the membrane is no longer relevant for breathability.
wayno wrote: i've walked on cold dry days with a rainshell on and even on the flat with plenty of wind, i built up sweat inside, gore tex can't cope with the sweat generated during prolonged exercise...
Well,... havent most people. point is though , you are still moving.
If you stop and wait long enough and ensure maximum temperature differential, you will become very dry inside the jacket.
People are impatient.
They don't want to listen to the facts . They just want to hear it can work. They expect too much from what is obviously limited technology.
Ever on the search for a one ended stick.