Regents Park, London
This year’s art fair is a jumble sale of mediocre paintings for the super-rich, while its Masters sibling hawks dinosaur skulls and sleazy 19th-century nudes. Welcome to the art market as its most grotesque

Naked people climb out of the earth and run around waving their arms and screaming, while someone with a bird’s head and wings plays the bagpipes. It’s my favourite artwork at this year’s Frieze but don’t go looking for this wildly imaginative outrage among the heaps of contemporary art at Frieze London. It’s a painting by a 16th-century follower of Hieronymus Bosch and is on view at Frieze Masters, the posher tent on the other side of Regent’s Park.

I’m sorry to say I was bored rigid in Frieze London. Many people attend, I imagine, hoping to be informed and excited by the newest, coolest art, but you’ll see more genuinely avant garde wonders in the Bake Off tent. There are endless paintings, none of which are much good, interspersed with photographs which tend to be a little better. The first thing here that held me at all was a two-metre-tall, inkjet print by Wolfgang Tillmans called Paul, nude, golf ball in which the naked Paul has his elbows on the floor and his close-cropped head bowed between them in apparent despair, while the white ball beside him eerily mirrors the pale flesh of his bony back. But it’s not new – it dates from 1994.

Modern Art, London
The late American took on liberal presumptions and the commercialism of Black culture, even dressing in white bunny ears and underpants

Seven squares are pinned to the wall, each one painted in the high style of American minimalism: pure, austere variations on a theme. At the centre of each is printed the phrase “negro idea” followed by an apparently random number (51, 37, 666). What is Pope.L, the late, great trickster of contemporary American art, getting at?

Perhaps it is a critique of how minimalism, with its ethos of art-for-art’s sake, excluded politics from art? Or a comment on how racial categories are as constructed (and as subject to fashion) as the theories underpinning contemporary art? Or is it a riff on how the edifice of western modernism is built on stolen ideas? Then again, maybe the deployment of an outmoded racial category is simply designed to discomfort the liberal pieties of those people likely to visit this art gallery just off Piccadilly.

The Back to Black singer’s books, shoes and jigsaw puzzles have gone on display. Elsewhere, a leaky Barbican and some gloriously gloopy sculptures can be viewed in London galleries this week

This year’s London photography festival takes you from the colourful streets of Kolkata to the grim isolation units of Guantánamo Bay

The late Christoph Schlingensief was one of German art’s great provocateurs. Can his B-Movie horror aesthetics still shock us into thinking anew about media power, colonialism, and the far right?

Christoph Schlingensief certainly knew how to provoke. “Fury at German play that shows Queen as a Nazi,” read the Sunday Express’s headline after Kaprow City first premiered at Berlin’s Volksbühne theatre in 2006. Drawing on the happenings of US performance artist Allan Kaprow, the play turned its attention to Diana, Princess of Wales’s death. In one scene, the then queen performs a Hitler salute. Another re-enacts the paparazzi chase that led to Diana’s fatal crash. Diana appears in bed beside two men with Down’s syndrome; and Camilla is pelted with animal blood. Schlingensief insisted the work was not meant as provocation but as an investigation into how Diana turned into a modern icon. But his art thrived on outrage, exposing the absurdity of societies that glorify their idols while consuming their lives as entertainment.

Kaprow City is at the heart of a new Berlin show – It’s Not My Problem Anymore, Deal With Your Own Shit – that revisits the artist’s legacy. In the Gropius Bau’s grand neo-Renaissance atrium, visitors encounter remnants of the carousel-like rotating stage he called the “animatograph”. Looking at this installation today feels like a glimpse into Schlingensief’s mind: a messy collage of childhood memories, violent fantasies and royal glamour.