Diameters not adjusting in 3D perspectives

[85769EMS]

Anyone know why the diameters of families are being held constant in 3D perspectives rather than being adjusted smaller as they approach the vanishing point?  Everything else looks correctly rendered in perspective in the scene, but I've got two different cylindrical lighting fixture families that get squattier and squattier the further away they are, because the height is (correctly) getting smaller but the diameter is being held constant.

Thanks in advance!

[constantin.stroescu]

it looks like you have inserted different instances of the same object.

• Select the lamps one by one and look at the instance parameters of the diameter (in Properties) to see if they are not changed . 
• Select a lamp (not in perspective view ) >Mode>Edit Family>Prooperties> Family Types>Name (check if aren,t different types there) and in Dimensions look at the diameter parameter if it is an instance parameter or a type one...
• could, also be a problem if you have used Array for positioned the lamps ?