Texture Layers.

 I found both of these images on Flicker,Water drop:Cubagallery. Flower:doug88888. I edited these two images together in photoshop and used the opacity tool set to 60%.

I found these two images on Flicker, Butterfly:TheblackAzar. Galaxy:KellytheZebra. I edited both these picture together in photoshop using the opacity tool set to 62%.