Flux curve of OJ 287 for April–May 2010. The Herschel-SPIRE data at 250, 350, and 500 μ m are shown alongside radio data from Metsähovi at 37 GHz (8 mm), the visible data in the R band from the Jagiellonian University archive, and SMARTS data in BV RJK. For clarity, the data in the visible and near-infrared are plotted in mJy so that they can be shown on the same scale as the radio and far-IR data (plotted in Jy). In many cases, the quoted error bars are smaller than the point size. No offset has been applied to bring the two main datasets in R onto the same scale, although there is evidence that on average, the SMARTS fluxes are ≈2% fainter than the Jagiellonian University/Mt. Suhora fluxes.