Recommand me a wide angel manual lens

I have a minolta 50mm and f1.8 and sony double lens kit.. I was at a restaurant the other day with my frens, the atmospheres was dim using slightly yellow light.. I tried with my 16mm 2.8 but the pic was dark even at 2.8 and couldnt capture a decent pic but if i was to use flash, it will attract unnecessary attention from others. I changed to my 50mm instead, the pic was bright and clear but only enough to capture single person portrait as we were just sitting opps each other in the small table ard 0.5m away. It was too close to take a pic with 2-3person in the pic. Is there any other manual lens that I can consider to take pic like this again, able to take wide angel and strive in low light.