Updated March 16, 2021.
Have you ever seen a needlepoint that amazed you because what looked like a solid color when looked at one way, has two shades in it when looked at another way? You find yourself thinking, as I did, how did they do that?
It isn’t very hard; they know how to use the property of directional light in threads. These threads look different depending on the direction of the stitches. It’s one of my favorite techniques. A piece I have sitting on my desk has this quality, and I marvel at how much it adds to the piece.
The pairs of stitches could be two directions of diagonal stitches, or they could be vertical and horizontal stitches; as long as the directions are opposite, you’ll see the color change.
Directional light is a property of some fibers and of the way some fibers are treated. Other fibers don’t have directional light. Silk and silk blends have directional light. Many rayon threads have it as well. Pearl Cotton has directional light, but floss has it to a much lesser extent. Wool and metallics do not have directional light.
In the Interlocking Chevrons Bargello sample above, you can clearly see how one color of Silk & Ivory looks like two different shades. It creates a wonderfully complex background.
A lovely way to explore directional light in threads is to make ornaments that are divided into quadrants, such as The Caron Collection’s free Byzantine ornament. Because the stitch direction changes in each quadrant, you’ll have two quadrants of each direction. If the thread color seems to change — that thread has directional light.
This version, sitting on my desk now, has directional light from all the Pearl Cotton. It isn’t as clear in the picture.
Because this ornament is so flexible, you could also use it to compare two threads, one with this quality, one without. Why not alternate wool and silk in the rounds? Or see which rayons have directional light?
If you can’t see the change when you look at your piece straight on, put the canvas at an angle and look at it from above. The change should be obvious.
Directional light is a lovely quality of some threads. It can make stitches look more complex, it can create exciting backgrounds, and it can be a great way to create some small needlepoint pieces. You’ll love having this trick in your repertoire.