Movie Render Graph Landscape issues

I have a foreground object, a lake behind it and a landscape behind the lake with foliage on it. I’m using movie render graph as i thought i’d give it a go. Just a two layer setup. I don’t even need holdouts. I just need the foreground with alpha and background. (The reason i need this is because of the water reflection issues, a whole other headache which i’ll leave out here :slight_smile: )

The background i can render fine ignoring the foreground objects. However the foreground objects refuse to render alone without revealing part of the landscape behind it, some kind of weird translucency issue with the landscape. However the landscape is not in the collection at all, so should not be visible. Anyone had anything similar? Sadly I can’t share any files as it’s for a client. How would you advise debugging this?

Over the last 5 ish years I haven’t yet successfully used alpha/layer passes using unreal render queue/ render graph without something going wrong. I almost always give up on it and build my own custom alpha PP materials for a luma matte which are cumbersome and slow… but at least they work.

My project has UDS, Landscape, Foliage and a foreground group of objects.

I’ve spent a day going through each of the various render pass features and none of them work. I literally can’t use data layers, layers, movierender queue stencil layers, object id , movie render graph or literally anything to get a simple separate pass in this scene. Stupidly I started the project in third person template so i’m stuck in world partition mode. The data layers don’t work either in the stencil pass. They render black.

I wonder if anyone knows a simple way to apply Post process materials to a large number of objects and then switch them on and off all at once very quickly? Then at least I won’t have to go through each object and apply them one by one. All i need is a simple black/white pass to make a luma matte for my group of foreground objects.

Basically i’m looking for a PPM that will identify foreground and background objects (eg by custom stencil or tag ) render foreground white and background black. Then i can add it on at the end for a simple quick luma matte pass. Any ideas?

I just used a custom stencil PPM and i can just choose which objects are included by changing their customDepth stencil value. Much easier than going through all the faff trying to work out why the render passes don’t work.

I can then turn it on and off in the post process volume if i need it. Annoying that this is necessary but I’m not spending any more time trying to work out why the movie render graph method is not working!