When trying to trace a fairly large file with sparse graphics - the trace function appears to lower the resolution significantly, resulting in a junk trace. If I clip a small portion of graphics and trace that, it works fine. Shrinking the file before tracing didn't work (by half), I couldn't shrink any more without losing the fine grained art. I was able to make this work using a different product(which I really don't like). I use trace all the time, usually on smaller logos, which works fine. I suspect there is something in their algorithm that reduces the resolution the program looks at based on the size of the file in order to save CPU time. It would be nice if that "handle" was available to the end user so they could decide to use more cycles or memory when needed. BTW, I tried to attach the PSD file - apparently, PSD files are not allowed. Why?
What sort of quality are you hoping to achieve? This is about the best I can get using the photo you uploaded