According to the tutorial of Ona, for Creative Techniques Challenge - Gradients + High Pass Filter

Anna Aspnes

ArtPlay Palette Bask
http://www.oscraps.com/shop/product.php?productid=30884&cat=383&page=1
ArtPlay Palette Autumnal No.1
http://www.oscraps.com/shop/product.php?productid=28662&cat=387&page=1
ArtPlay Palette Autumnal No.2
http://www.oscraps.com/shop/product.php?productid=28663&cat=387&page=1