A true understanding of star formation must come from the combined study of galaxy simulations and observational data: the physics built into our simulations are driven by observations. It is therefore critical to fully understand the emission tracers we rely upon. Synthetic observations are the key: they teach us how different emission tracers change with environment and, through comparisons with observational data, how well our simulations describe the real Universe. Through coupling the stellar population synthesis code SLUG to galaxy simulations, we can generate synthetic star formation rate tracer maps. The maps we generate have different metallicities and star formation rate surface densities, so we can explore and constrain the environmental effects on the timescale for which emission from different star formation rate tracers is visible. Real observations are often affected by extinction; it is therefore important to understand the extent that extinction could change these observed star formation rate tracer lifetimes. Using these timescales in observational application of “the uncertainty principle for star formation”, a new statistical method used in constraining the tracer lifetimes, it is possible to constrain the durations of different evolutionary phases of the star formation process and so better understand the physics of star formation and feedback on the cloud scale.