Having this problem for several months. I have displacement map image sequence for an ocean but I cant use it in the "image" node to plug it into displacement for my flat grid. I always always always get the same error for months, "can't have channels which depend on time".
I tried several build of Houdini 18.5 and whatever is the latest of HtoA in the last 6 months.
I tried a material network in both mat and SHOPs context and it doesn't differ.
I tried $F, $F3, $F4, ####, `@Frame`, animated parameter outside of the shader network that is referenced inside the "image" node.
All these methods are giving me the same error and I am stuck with mantra for oceans.
Houdini current version: 18.5.633
Arnold current version: 6.2.1.1
Screenshot of the problem: https://prnt.sc/1qvjdf2
I will give it another try with Houdini 19 and Arnold 7 later.
UPDATE: Apparently this error is only for the IPR, I can ignore it and render a full sequence to disk and it will work just fine. The problem now is that the IPR refuse to fire up/ render anything as long as I have that expression in an Arnold material builder.
Now I can render oceans but I cant use the IPR 😞