Spatial resolution versus z for a rest frame wavelength of 200 nm (yellow) and 8 μm (red) with the JWST, and at 100 μm with ALMA for baselines of 150 m (blue) and 1 km (green). We adopted the cosmological parameters of Planck Collaboration XVI et al. (2014). The solid lines show at which redshifts the observations can be carried out. With the JWST, observations below 200 nm are not possible below z = 2, while observations beyond z = 2.5 are not possible at 8 μm. Conversely, the rest frame emission at 100 μm cannot be observed with ALMA below z = 3.2. There are several gaps at longer wavelengths corresponding to the gaps between different ALMA bands. These bands correspond to those available for cycle 2. Band 10 will strongly improve the capabilities of ALMA to map the main infrared star formation bands at moderate redshifts, while band 11 will allow us to probe the peak of dust emission down to z = 1. Finally, the hatched area corresponds to a resolution lower than 1 kpc, where there may be a strong effect on the measure of star formation.