i know that this maybe a stupid question and in maya i would easily do more substeps but that seems not to work here - i know i am doing something wrong so please one have to light me up.

you see in the picture below that gravity ist causing a stepping issue on my flip sim (easy setup only flip and gravity) - i know that this is caused by frames, one frame it is here next frame one more down - but can someone tell me what i have to do to get a better interpolation between the frames.

cheerz and thanx
de Heavy

You can add your substep here too, on your dop network node itself. but the stepping issue is pretty natural and you can fix it from your source. if you using a circle with some points scattered on it you should add a point jitter sop in a specific direction to reduce this issue.

Another possible solution is to use the Motion Blur tools on the Fluid Source SOP. It trails the geometry back in time, and is far faster than increasing substeps on the sim.

You can also us a Trail SOP manually, prior to going into the Fluid Source, to get this same effect.

Here's a hip file, hope it helps!