Diver0001:
I wouldn't bother if I were you. CMAS is known world wide and in France PADI is pretty much laughed at (the French are nothing if not proud of their CMAS). In all honesty crossing over would add nothing of value to your training or to your ability to find dive locations abroad.
R..
I know that the PADI card is almost useless in France, I was just wondering if I dive abroad. From all the answers, it seems that not.
About what is required for certifications, I do not know if there are differences between the various agencies affiliated to CMAS. To get my 2*, I had
-to swim 500m withe weight suit, weight, fins, mask and snorkel
-to free dive to 5m deep, horizontally 10m then up with the same gear
-to swim 250m on snorkel but withh all scubagear on (full bottle, empty BC, so slightly negatively buoyant)
-to jump in water mask on hand (diving gear on), and have the mask properly put and empty when surfacing
-to be able to dive to 20m beside a line but without touching it, and staying neutral (almost) all way long, then stabilise 1M above the 20m floor
-to be able to go up from 20m deep at proper speed and stop at 3m without depth gauge or computer
-to remove mask and empty it at 20m depth, in 12 C water (my club requires that we pass the exam in cold water, but it is not required by CMAS)
-to be able to come back to surface from 10m without octopus, exhaling all long.
-exchange of signs at 20m depth, followed by proper reaction: I must be able to bring back safely to surface a buddy who has a problem and cannot handle it by himself -if he is still conscient and able to keep a regulator-octopus in mouth. ->management of 2BC at the same time To be able to bring back an unconscient one is next level.
-some orientation
-a lot of theory, on physics, physiology, diving accidents (causes, prevention, symptoms, treatment), deco procedures with tables, gear maintenance, french law on diving.
Some of these are reminders of 1* requirements, only done in harsher conditions, or deeper, or longer