Improve shading, simplify shapes, and use Notan for drawing and painting
In art, a value (or tone) is how light or dark a colour is. If you're learning to paint or draw, doing value studies is an excellent place to start. These small, loose sketches in greyscale show where shadows fall and highlights appear. These are particularly useful when the subject is more complicated and it's hard to see through the colours to show the subtle shadows.
Value Study is a paid app with a very low priced yearly fee or a lifetime purchase available to access all features. There are some free images from Unsplash available to preview the app before purchase.
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If you're learning to paint or draw, black/white notans and more detailed value studies are a surefire way to improve both your artwork and how you visualise references in your mind. People often use photo editors to convert a colour photo to black and white... this is helpful, but this app goes further.
By using Value Study, you can flick between levels of detail. Maybe you want to start with just black and white to get a base down, then add in extra values one by one to build up your understanding of the reference you are studying.
You can even take it a step further and select all areas with matching tones. Click one of the values along the bottom in the greyscale palette to see all areas that match it in the image, so you can focus on one value while painting it. For example, in a portrait, this could mean seeing how different parts of the body have the same amount of shadow despite potentially looking wildly different when viewed in colour.
Value Study is a tool, not to replace your value studies but to enhance them and significantly help beginner artists know where to start when looking at complicated reference imagery.