Media where you can’t erase easily like chalk pastels are great for helping build strong lines. Strong lines mean the drawing feels better to people and it feels more finished even if the proportions are fairly off. It’s great for stretching poses and working on exaggeration.
I know the kind of smudged blending you’re using probably feels comfortable from working in pencil. I’d suggest resisting it though while you get comfortable with the way the new tool works. It takes a lot of time to build strong dark areas when you smudge. The more you can trust your lines to be good enough, the more your shading will seem vivid. Work with the tool not against it.
Unlike ink, chalk pastel will let you do very light lines. And for long poses the light lines from ghosting a gesture drawing can help you get the soft shadows laid in without having to go back later.
Chalk and chalk pastel are really old media. They’re favorites of Disney artists and the greats of the Italian Renaissance and everything in between. It can be really bold or very delicate, and it takes a lot of skill.
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