I am wondering why there seems to be such big differences in the precision of execution of the tritium hour markers (non redialed of course) even in case of same model and same production period. At the two extremes, we have on one side, thick, foamy, rounded, and relatively unprecise markers, like those of my 145.012-67, on the other side, aoparently flatter, sharp, higher precision markers which perfectly cover the rectangular white marker underneath. Can this variation be due to the production standards achievable in those years? Were diale manufactured in different sites/by different companies? On which extent does it depends on the aging process? There is also the possibility that pictures influences remarkably the perception of the quality of the markers, which at naked eye is not easy to judge. I'd like to hear your thoughts. A picture of my speedy.
I think circumstances also play a big role. Tritium that has been around temperatures of 30 degrees celsius (for instance South America) for the majority of its 50 year life, will behave differently than tritium that has been in very cold conditions (Sweden for example). Also exposure to moisture has a big effect, as well as sunlight I think.