How long should Lumn last on a watch? little bit disappointed with my Christopher Ward, charged with a UV torch its lovely and bright but completely gone within an hour.
I've made it my life's mission to appreciate good lume in any watch I buy so feel I can put forward my experience here.
There are a couple of things to note with lume and how long it lasts. The brand doesn't really matter, it's how it's applied (layering) that dictates how long it lasts as well as the compound "day colour". I don't know what CW watch you have but if it's anything like standard couple of layers of C1/green unbranded lume like most Longines then it won't last long at all and may well be invisible within the hour.
I was so furious with my Longines HydroConquest lume once that I sent it to Detroit at MCWW to be re-lumed with heavy blue NoctiLumina and it came back with blue lume that lasted several hours with an initial brightness that lasted 5-10 mins and then slowly dimmed to a visible glow for several hours after. Both my current watches use lighter layers of C3 and BGW9 but are heavy enough to still glow in the middle of the night and be visible with dark adjusted eyes so personally I am fine with this.
Since then I've only had and seen a handful of watches with lume that can be compared to the MCWW application. Tudor Pelagos used heavy BGW9 which was nearly on par, and the Marloe Morar Black Edition which exceeded both of those watches with a custom compound that was bright for 5 hours and was visible in the middle of the night having seen no light.
Expectations of lume brightness and longevity will be solely down to how much the maker cared about lume for that particular watch and not the brand in general as it will vary insanely in my experience between models and how much time/money the maker wanted to dedicate to good lume. Doesn't matter if it's a dive watch or dress either, all down to effort on the maker's part.