Comparison of SN 2018oh to models with and without ⁵⁶Ni shells in the outer ejecta. From left to right, panels shown the g-, V-, and Kepler-bands. Observations of SN 2018oh are shown as black points. Non-detections and detections of < 3σ are shown as downward triangles. Our fiducial model is shown as a grey solid line, while models with ⁵⁶Ni shells are shown as coloured lines. Based on comparisons to our models, we infer an explosion date of MJD = 58144.1, which is shown as a vertical dash-dot line. A model with an extended ⁵⁶Ni distribution relative to our fiducial SN 2018oh model is shown as a dashed line. The epoch of our spectral comparison is shown as a vertical dotted line. In each panel we show a zoom-in of the first four days after explosion. We note that this does not cover the epoch of the spectral comparison.