Buying guide
Choose a flat wash, mop, or quill
A rectangular sky and a loose cloud edge call for different brush shapes. Choose the edge you want to paint first, then think about how much of the paper you need to cover before reloading.
What to compare
Start with a flat for a straight edge
For a rectangle, a flat face helps you lay down a broad band. Use the narrow edge for a finer line. A wide flat is useful on a broad sheet, while a narrower head gives you more room to turn around the edges of a postcard study.
Use a rounded head where the edge needs to turn
An oval wash or mop suits soft shapes such as clouds and pooled foliage. A quill has a fuller belly for carrying paint and narrows at the tip. That makes it worth comparing when one stroke has to travel from a broad area into a small space.
Choose capacity relative to the paper
A larger belly carries more water and paint. For a narrow wash between pencil lines, a smaller head can be easier to place. When your main difficulty is repeatedly reloading halfway across the page, compare a fuller head before replacing your detail brush.
Questions before buying
What works well for a clean horizon?
Start with a flat wash. Its straight edge is easy to align with a horizon or masking tape, and its face can cover the area above it.
Should I use a mop or quill for loose clouds?
A mop works for soft rounded shapes. Compare a pointed quill if you also want to pull the edge into a narrow turn with the same loaded brush.
Is a brush labeled three-quarter inch always exactly that wide?
Treat the label as the maker's size designation. If the maker provides measured width, use that figure to compare brushes from different lines.