Process for making moving water on a white background pop

There is almost no information in that shot. This is the most I could get from it. You are going to have to reshoot if you want to have anything resembling a water stream you can overlay onto another shot.

You need a shot with a nearly full histogram. You just don't have any data to work with to generate a matte. The only thing you have any chance of pulling is a matte for the stream before it hits the card.

That will be a crazy shot to deal with, to be honest. The first thing to do is to stack a bunch of duplicates of this with belnding modes like Screen or Add, while applying different Levels and Curves adjustments on each layer to get rid of the greyish base. That way you can capture the highlights at least. Rinse-repeat for the few shadows by using Multiply modes. Then carefully re-assemble the shot and fine-tune it further. Subtle adjustments with Find Edges, CC Vector Blur or an adaptive blur from RevisionFX' SmoothKit package might also help. If you're feeling adventurous, it may also be worth experimenting with bump map and normal map generation and conversion in Photoshop, 3D programs such as Blender or game tools like Unity to extract soem edge info and perhaps use the maps you would generate to amplify your shot with soem faux lighting. It's pretty much a case of grabbing for straws, given how little contrast there is and it's going to be a lot of work.

Mylenium

Agree with rick. Show us a reference frame/ screenshot and then we can talk. Maybe it can be fixed, mnaybe it can't. This may be one of those cases where actually shooting in color and tinting the water might have helped a lot to extract mattes or make the water appear more dense.

Mylenium

We would have to see at least a still frame of the shot to give you any meaningful suggestions. Seeing the actual video would be best. There are hundreds of different techniques for creating the kind of matte you are talking about. Separating anything from the background can be easy or nearly impossible, but if you have enough patience, most shots can be handled in one way or another.