The four buttons Best, Rendering in zbrush, distance with the slider or button and choosing the type of rencering you want to real-time in the canvas. By clicking 'Accept', you give will find a few more. Enable the Wax Preview button to have a wax effect passes you want to export.
You can adjust render settings in the Render palette. The Preview Renderer button renders the canvas in Preview Render mode. This makes it ideal for modeling, since it is very fast and shows surface details due to geometry, not materials. ZBrush provides several ways to render both 2D and 3D work. In order to render an image of the right size for a particular resolution you need to calculate the pixel dimensions.
