Setting blending modes and adjusting opacity

…Here in After Effects, once I've got my images imported…and stacked in the timeline, I can set their blending mode.…What I've done is to show the blending modes here on my timeline.…I've right clicked on the title bar and chosen columns and modes.…And this allows me to use the drop down where it says normal.…And change over the blending mode easily.…I set my specular path to screen then drop down the…blending mode on the ambient occlusion and set it to multiply.…Here's how this looks and why we like to stack these on here in post.…My beauty image is good, although the walls are floating just a little bit.…

When I add on the ambient occlusion, the multiply, multiplying the gray in, and…essentially taking out the white, adds that…grounding darkness in on all my objects.…So I get a good darkness going on, right under…the stairs, and all of my fine detail pops out.…Screening over the specular pass then, allows that shine to screen over.…And effectively deleted any black in screen.…Having black in there is like dividing by one.…