My experience has finally gotten me past the feeling that I've ruined a figure or vehicle by glopping on the Gesso, and I've provided some photos to show how the Gesso shrinks to re-reveal all the details of the model beneath.
I use Liquitex Gray Gesso and a fairly large brush, even when priming 15 mm scale. I've dedicated a single, cheap artist brush for the Gesso, as I'm not sure if it would contaminate or otherwise harm one of my regular painting brushes.
|Liquitex Gesso, cheap artist brush, and two Battlefront Panzerjager IV|
I chose the Battlefront Panzerjager IV as a Gesso priming demo, because it has plenty of detail, including scuplted Zimmerit. Added to the one tank hunter are a few extras (crate, tarp, and jerry can) from Command Decision; the other has two crew members looking through the hatches.
|Battlefront Panzerjager IV ready to prime|
These next two photos were taken approximately three hours after the Gesso was applied. The material has already shrunk to fit the model underneath, and you can once again see the detail. The transformation can best be seen with the crate on top and the tools on the engine cover.
I'll continue to wait at least 24 hours before painting.
As an additional reference, I've added a photo of some 15 mm Battlefront Fallshirmjager Panzershreck figures that were primed with Gesso a few days ago. All the detail of the original sculpt is there.