Zenithal Undercoat vs Slapchop differences explained

Zenithal undercoating and Slapchop are two painting methods that are quite similar. I was confused at first and thought that they were basically just two different names for the same thing. As I have explored them both I have found that there are some distinct differences between the two methods. I am going to lay out the differences that I see here in this article.

Zenithal Undercoating Method in a Nutshell

Zenithal priming, or undercoating, is a technique that has been around for decades. Zenithal undercoating is primarily an OSL (Object Source Lighting) technique of undercoating your model that sets the source of your light as the sun. It is primarily done using the natural spray pattern of an airbrush from above to establish the places where light would naturally land on your model. You need a lot of contrast for this method so you will typically only use two colors, most commonly black and white. Thin layers of acrylic paint are used over this undercoating to allow it to affect the values of the paint that is over the top. If you want to dive more deeply into zenithal priming you can read all about it here.

Slapchop Method in a Nutshell

Slapchop painting is a technique that has been developed recently to take advantage of contrast style paints. Slapchop painting starts with priming your model in black just like zenithal undercoating. It diverges from zenithal on the next step. It uses an intermediate color, typically gray, to cover the vast majority of the model. By dry brushing the model, you are going to cover most of the model in gray leaving only the deepest recesses black. You are going to drybrush in all directions rather than top down only as in the zenithal method. The model is then dry brushed with pure white in the areas where the brightest highlights will be located. Finally, the model is painted using contrast style paints to take advantage of both your preparation and the properties of the paint itself. If you want t explore the slapchop painting method in more detail I have an article that you can read here.

What method should you use?

Glad you asked that. I have made a chart outlining the differences between the two methods, but for me, it comes down to two questions, are you planning to use contrast paint, and do you have an airbrush?

If you are planning to use contrast paint, then the Slapchop method is for you, if you aren’t then zenithal undercoating is great, but only if you have an airbrush. Yes, it can be done with a dry brush, but that is for another article on another day.