I've read about it at the SM Forum, IIRC. I think it was here as well.

The Prefitter is a figure with fitting Morphs for several figures. You load your garment into the Scene, conform it to the Prefitter and copy the fitting Morphs to your garment. You unparent the garment and have a fitting Morph for the figures you selected in it. Without parenting, you dial in the Morph in the otherwhise zeroed garment and it will mostly fit your zeroed target figure. After that you can use the Fitting Room to make it conforming.

This work better than fitting with the fitting room, because the Morphs in the Prefitter are created with Marvellous Designer's Cloth Simulation. It does not move the Cloth like the figure would move but rather how a garment on the figure would move. The results aren't perfect, but way better than with the fitting room. Usually some strokes with the Morph brush are needed to correct the garment where the Transformation isn't perfect - you do that before the fitting room.

I do have ZBrush, I used to refit my clothes with that, but the Prefitter saves me a lot of time to get the clothes 90% correct. For me it's wll worth the Money.

Link to the Prefitter

Link to the Extension for La Femme

A ship in port is safe; but that is not what ships are built for.
Sail out to sea and do new things.
-"Amazing Grace" Hopper

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