Dried paint inside the tube can be reactivated with water because each pigment particle is encapsulated in gum arabic. Try adding some water back into the tube a little at a time until you have the desired consistency. Alternatively, you can cut the tube away from the dried paint and use it as you would use a half pan.
Watch to learn more! This video clip is from a Zoom session from the LIVE with John Cogley series.
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