Sketch presets in Poser require the render dimensions they were made for.
For instance: you render a Preview to 2800px, to set the canvas size, then switch over into Sketch Designer with Crtl + Y. Sketch Designer thus loads with a big 2800px canvas and lets you design Sketch presets for that size of render. These saved presets should be saved with a title that indicates their required output size and requirements. For instance – “Horror inking at 2800px – Skydock light – no CBM on” (seen below).
If you then start Poser another time, and try to Sketch render with the same preset — but to, say, 3600px render size — then part of the sketch effect will be truncated at the edge that is ‘expected’ by the preset. As you can see here…
The lines will also look different. Here they are more closely packed than the looser preset was designed for, because they are being run onto a larger canvas.