Poser Gravity Quirk Around

Poser does have an alternative for gravity calculations. Its in menu > Scripts > Utilities > Gravity, at least in mine. 

So I took a cube, raised it 19,6 mtr as in the cloth experiment, and fired the script. It created a nice set of Y-Move keyframes, the animation window showed a nice parabolic curve and all positions could be read out as Y-positions on a per frame basis.

I could see the cube felt faster than the cloth (I put them next to each other) and the cube hit the ground at about frame 56 instead of 60.

So I did velocities and accelerations again and I measured a gravity acceleration of 0.01310 with an accuracy within 2% (as I could read out the positions, measurement errors were less than with the cloth).

So, this way of dropping things if off the Earth gravity constant, and hence off the Cloth Rooms value too. This means that when you've got cloth and props and drop them both in a no-air environment, the cloth will lag behind for this reason only. So that's the quirk. It annoys me. No one uses the script for stills but this effect is considered harmful for meaningful animations in scenes with cloth and props. Like in story telling.

Where does this value come from? I don't know for sure, but I do know this:
Earth gravity converted to 30fps reads 9.8 / 900 = 0.01089
Earth gravity converted to 25fps reads 9.8 / 625 = 0.01568
The average of those reads 0.01329, which is within the 2% accuracy of the measured 0.01310.  So my wild guess is that someone out there could not decide how to convert earth values into Poser, should I take NTSC/60Hz/US-UK-based 30fps or should I take PAL/50Hz/French-Europe based 25fps? So he took a middle position. It's not a bug, it's a feature.

But unfortunately, someone else out there decided upon 30fps for the Cloth Room.

I don't know, I'm not pointing fingers. perhaps some can just change this one parameter in the script.

happy dropping :-)

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Usually I'm wrong. But to be effective and efficient, I don't need to be correct or accurate.

visit www.aRtBeeWeb.nl (works) or Missing Manuals (tutorials & reviews) - both need an update though