How do you create a smooth graduated fill between two colors using thread? I am studying with fiber artist, 
Carol Shinn, this week and we are learning how to do this with freestyle machine embroidery.
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| A yellow green to red violet 5-step blend. | 
Here is the stitch-out from yellow green to red violet.
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| Color blend stitch-out in Carol Shinn's worshop. | 
Today we used a photo transfer process to get the image on the base fabric. There are many colors and shades of thread used for the stitching.
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| Free-motion stitching with image transfer. |