Here is a how-to for Ebony woodgrain. It is a 3-step process to create this rich and heavily-grained wood. If you use a fast drying medium like matte medium, it’s possible to do all 3 steps in one day — or at least 2.
The example in this post had an satin oil basecoat. However an eggshell latex (like BM Aura) is perfectly fine. Sand and dust before glazing. The first step is in this particular wood is the flogging. We’re missing pictures, but check out this flogging video for a tutorial. This step adds the look of wood pores which instantly gives a “woodsy” appearance. The whipping motion of the flogging brush is the only tool that can achieve this background. Mix a glaze: fast dry matte medium plus colors; raw umber, black, and touch hansa yellow to brighten.
Once dry, the major grains are painted (wet-on-dry application) with a heavily pigmented glaze mixture: slow dry low-viscosity medium plus colors; black, vandyke brown, and touch trio (transparent iron oxide) to brighten. The applied grain must be parallel lines (but not perfectly straight) and the grains should be varied in size and distance between. A brush like the tooth veinette with a sparse amount of long, stiff hair is the best tool. For a better visual on this technique, see this veinette video to see how the tooth veinette brush makes this prominent but delicate print. It is important to fully load the brush for such a large print.
Soften the grains with a badger softener. It is very important to soften in a thoughtful manner. Soften in one direction at a 70 degree angel to get the desired effect. Don’t over-soften.
Pass over the surface with the same brush one more time using less of the same glaze. The goal is to create finer (double) veins within the first pass and with a slightly different angle. Soften these veins lightly.
Once completely dry, apply a transparent overglaze to the surface with a glazing brush. Glaze contents: slow dry low-viscosity medium plus colors; burnt umber, vandyke brown, touch trio and black. Looking for a warm and deep transparent tone. Stretch (even out) the glaze with a spalter.
Let dry and varnish (dark woods look better with a glossy finish). I’ve added a trompe l’oeil effect on this baseboard-sized sample. See this post for a how-to on trompe l’oeil molding over a dark wood.