Okay, here are 6 renders, without AA bloom.
The times:
Box - 0:46:32
Tent - 0:47:42
Narrow Cubic - 0:48:28
Narrow Cubic B-Spline - 0:48:56
Mitchell-Netravali - 0:48:49
Catmull-Rom - 0:48:31
I chose to render a simple scene the still takes a relatively long time, to see how the rendertime is affected. On 3 quarters of an hour, one or two minutes don't matter that much.
The differences in effect can clearly be seen, close up, but perhaps even more so in the distance.
Narrow Cubic B-Spline gives the smoothest results in this case.
Next post will have the same test with AA Bloom on.