I use the end of an old airbrush needle of a retired airbrush. I'll give it a good shake then I'll stir it vigorously for 30 seconds.What are you stirring with? Humbrols always been thick for me... I don't use it really. But years ago like when I painted Wasted Fetts helmet for example it was really sludge.
And yeah, no matter what paint I've used, yellow has always been a problem. Killstripes first time round took forever and trying to get that gradient right first time was so stressful.
I experiment a lot; it tends to depend on how thick the paint is to start with. Even by lightly dipping my brush in thinner before the paint gives me the same transparency issues with Humbrol. It's a shame, because I work at a place that sells them, so I get a discount on them. We do have a limited stock of Tamiya which I've found to paint better, but I've not seen any colour lists for Boba with Tamiya and I don't think we have all the colours I'd need. I wish we had model masters, but I've never seen a bottle on this side of the pond.To which consistency do you thin your paints when you apply them with the brush? Same as the bluemilk airbrush-consistency?