import graph3; 

size3(150,IgnoreAspect);
size(8cm,0);

limits((0,50,0),(10,60,2)); 

triple m=currentpicture.userMin(); 
triple M=currentpicture.userMax(); 
triple target=0.5*(m+M); 
currentprojection=perspective(camera=target+realmult(dir(60,50),M-m), 
                              target=target);
                              
xaxis3(Bounds(),OutTicks(endlabel=false,Step=4,step=.5)); 
yaxis3(Bounds(),OutTicks(Step=5,step=1)); 
zaxis3(Bounds(),OutTicks);