Before last year’s criminally ignored The Florida Project, Sean Baker made headlines by shooting 2015 feature Tangerine on iPhone gear (the director used 3 different iPhone 5s). Indie authenticity suited the low-key story of pair of transgendered prostitutes on the Sunset Strip, capturing the forced street intimacy and, when tilted skywards, the expansive, beautifully festive colouring of one-crazy-night Los Angeles. Now Steven Soderbergh, no stranger to doing things his own way, has shot his new film Unsane with an iPhone rig (iPhone 7 Plus in 4K, with the app FiLMiC Pro). No doubt it helped keep some costs down — again, Soderbergh…