This is a very quick and easy step by step.There are a lot of brushes for photoshop out there for creating rain but I have created a section and attached it here.Just use it with blend setting of "SCREEN" over your render and it will come through.
For the splashes the process is as follows:
1.Open the render and create a new layer called splashes.
2.Using one of the default "star" brushes(see attachment for which one to use)paint a line of stars along the top of the walls.
3.Add a motion blur at 90 degrees of between 30 and 40.
4.Add a gaussian blur of about 7
5.play around with the opacity of the layer but thats really it.The effect is that of rain hitting the surface and bouncing back up.Be careful in the strength of the effect that you use,it should be less for softer rain than for a heavy rainfall.
You can use the same technique on vegetation (if you lighten the areas locally where the rain hits the leaves it can make the effect more pronounced,as if the leaves are so wet they are almost fully reflective)
Hi Irwanwr,yes pretty much done with the holidays now but it was great while it lasted.
