My warmest greetings! On this page, I will show you how easy it is to create photo-realistic image of waterdrops with only Adobe Photoshop and a mouse. Let's start with new document (I usually set size to 3200x2400 pixels) and fill iw with dark-blue.

Next, add some 3D effect. For this, draw a light-blue line in new layer, using very wide brush (here around 1000 pixels width).

Then, use Gaussian Blur filter (with large setting such as 200px) in order to, well, blur :)

Then merge these 2 layers (Ctrl-E), and apply a couple more effects - first Noise (not much) and then Paint Daubts (again, only a bit).