In my two samples above (floral images from JustRite Stampers' Beautiful Day stamp set, both stamped with Tsukineko Memento Tuxedo Black ink on fabulous X-Press It Blending Card!), I've used two different ways to color objects white, using Copic markers. The first method is to start with a very pale (quad 0) marker color as your base coat on the flowers and then add the deeper shades of color to the centers of the flowers. Here, I used R0000, R81, R83 and R85 to make these lilies resemble my favorite Star Gazers:
(Greens used were YG03 & YG17). You can also use the Colorless Blender marker to remove color from the outer edges of the flowers, to make them appear even whiter. But I find starting with the R0000 gives a better, less streaky blend than the Colorless Blender:
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If I hadn't added any shading to the white flowers, this is what they would have looked like:
Another tip to coloring white things is to place as much color around the white object(s) as possible -- this will give more life to your project. As you can see in my second example, there are a lot of greens around the white flowers (YG03, YG17, YG63), the pink bow (R81, R83, R85), and I airbrushed the background of the image with Copic Y32. All these things draw your eye to the white flowers and make them the center of attention!
Many thanks to the Copic Oz team for asking me stop by today . . . I hope you enjoyed the tutorial! ~ Sharon