I tend to go through my air faster than others in the group and on a few occasions I have had to signal to the divemaster that I was low on air;
This is good that you are monitoring your air. It is normal for a new diver to suck down his or hers air.
twice, in my opinion, dangerously low (below 500 psi).
Dangerous is a subjective term. This will depend where and depth you are at. A diver who has 400 psi left and is at the safety stop then one would not necessarily consider it dangerous. Additional information is needed to comment any further.
When I guide divers I tell them, if they feel they are breathing their gas quicker than others then ascend and dive above the group.
The best divemasters (in my opinion) have regularly monitored all the divers in their groups, asking, with signals, for a check on air levels. I may do a night dive on my next trip, but I am feeling somewhat anxious about how the divemaster will keep tabs on us "hoovers?"
The idea it is the dive guide's responsibility to monitor everyone's gas consumption is a fallacy. When hear or read this type of comment the first thing that comes into my mind is "great, a diver who isn't willing to take responsibility for his or hers diving".
As a guide on a deep dive with a group I maintained an awareness of peoples gas consumption. On shallow guided dives I inform the divers they are to let me know when they are halfway through their tank. With that info I can determine whether or not to cut the dive short or carry on with the dive plan. Nevertheless, I always inform divers monitoring their own air is their responsibility, not mine.
What would you who have done night dives want from the divemaster?
When I learned to dive I was taught to monitor my own gas consumption. If need be ascend to a shallower depth and dive above the group. Or, which I had to do in my early days, ascend to the safety stop, after alerting the dive guide, to end the dive.
I may do a night dive on my next trip, but I am feeling somewhat anxious about how the divemaster will keep tabs on us "hoovers?"
What exactly are you referring to; monitoring your air and donating to you if need be or keeping you with the group to prevent getting lost? What is it that you are expecting the guide to keep tabs on? Be specific. Your earlier posts imply gas monitoring. Is that what you are replying to.
When I lived in the tropics there were two types of divers, those who were not certified and those who were. Those who were not certified took the resort course. Basically I held their hand. That was fine, that is the type of dive they signed up for. The other group is the certified divers. In this group I monitor them for safety. but do not hold their hand. Gas consumption, staying with the group, maintaining situational awareness, sticking with their buddy was their responsibility. My responsibility was safety.
Remember, you are not the only diver in the group. If each diver was wanting the dive guide to "monitor" each and every diver then deal with a problem, such as running out of gas, leaves the rest in a precarious situation. Each person needs to take responsibility for him or herself. To gain additional experience and training take some continuing ed classes. They will help.