Ex vivo calibration of GCaMP6s and GCaMP6f signals in soma and apical tuft dendrites of layer 5 pyramidal neurons from the mouse primary visual cortex (V1). We examined the relationship between neuronal spiking and calcium event amplitudes in proximal and distal neuronal compartments, ex vivo, by combining calcium imaging and whole-cell recordings in acute cortical slices from mouse V1. We imaged the soma and distal apical dendrite (nexus) of GCaMP6s- and GCaMP6f- expressing layer 5 neurons whilst driving neuronal spiking either by somatic current injections (somatic stimulation) or L1 electrical stimulation (dendritic stimulation). Dataset corresponding to Figure 4 and Figure 4 supplementary 1.