Ember has an impressive ability to structure material with far more precision than many other 3D printers. Depending on the resin used, it can print layers between 10 and 100 microns thick with XY resolution of 50 microns. While low layer heights are often useful for printing certain structures, in everyday use, I like printing at higher layer heights for the following reasons:
To demonstrate the relationships between layer height, print time, and print quality, I chose two very different geometries: a lattice of my own design and a scapula from Thingiverse (both attached). The lattice is composed of delicate 500um struts while the scapula is a complex organic shape. I scaled both to a height of 42.54mm (40mm + 2.54mm of supports for the scapula) and then printed each files at 25um, 50um, and 100um layer heights in Autodesk's standard clear prototyping resin.
As can be seen in the photos, both geometries printed at all three layer heights and for many applications, higher layer heights don't diminish print quality.
Because increasing layer height increases the amount of resin that must be cured with each exposure, the exposure time must be increased as well. A further complication is that different features often require different exposure settings. Fine "positive" features, such as the lattice struts, require a slightly longer exposure time than geometries with higher cross sectional areas, like the scapula. Additionally, I turned off "variable exposure" for the lattice to ensure full curing of the small struts. A can be seen in the graph, it was nearly 200% faster to print at 100um layers than 25um layers.
Scapula print times and exposure settings:
Lattice print times and exposure settings: