Gwyneth Paltrow has a new neighbour. On the same block in Notting Hill as Gwynie’s Goop store, with its This Smells Like My Vagina scented candles and must-have child-calming essential oil sprays, a shopfront has been taken over to display a poignant series of self-portraits by a rather different woman. Khadija Saye died three summers ago with her mother in the Grenfell Tower fire. Much of the 24-year-old artist’s work was destroyed in the blaze, including three tintype images from a series of nine called ‘in this space we breathe’. The other six were displayed that summer in the Diaspora Pavilion at the Venice Biennale in Saye’s first major international exhibition.

Now, poster-sized silkscreen prints from that series have been installed in the shop windows of 236 Westbourne Grove. One can study these works online or through a special app, but to see them in this affluent neighbourhood a little over a mile from where Saye lived and died is more than worthwhile. In death, Saye has a corner in the Notting Hill of Hugh Grant, David Cameron, yoga franchises, decorous pavement cafés and eye-wateringly expensive real estate. Saye’s intimate, austere, spiritual images, steeped in her Gambian heritage, serve as something she perhaps never intended, namely a weighty rebuke to W11’s froth of conspicuous consumption.

Each poster is a reproduction of a 250mm x 200mm tintype original. Tintype, popular in the late 19th century, involved producing a photographic image on a thin sheet of metal coated with lacquer or enamel. Saye produced wet-plate collodion tintypes, according her 21st-century self-portraits the aged look of historical documents. Fitting, since she was delving deep into traditional Gambian spiritual practices.

These self-portraits depict the artist holding or wearing scarcely decipherable, very nearly surreal, artefacts. In one, textile petals seem to grow from the artist’s mouth; in another, a handful of finger prostheses as formidable as sprinter Gail Devers’s nail extensions conceal the artist’s face; in a third an arm reaches out from beyond the frame and places some conical object at the base of the artist’s neck as she bows her head. For all my mystification at this iconography, I felt myself in the presence of the religious impulse or, as Saye put it, ‘the deep-rooted urge to find solace in a higher power’.

While you could hold the original tintypes in your hand like Hilliard miniatures, these posters make the intimate monumental. In only two images from the series does Saye confront our gaze. It’s an uncanny experience to meet those eyes. At once, I felt for all the world as if I had stumbled across venerable images of a 19th-century Gambian woman communing with some divinity. And at the same time I saw her as a guileful, soulful 21st-century Londoner knowingly immersed in roles that she created.

I cycled from Notting Hill to the Marian Goodman Gallery in Soho where another artist has spent her career trying to work out what portraits do. Khadija Saye said: ‘I wanted to investigate how a portrait could function as a way of announcing one’s piety, virtue, soul and prosperity.’ Dutch photographer Rineke Dijkstra’s latest portraits are about how we try and sometimes fail to announce ourselves. And, you’d think, how parents try to control what gets announced in family snaps. A Russian girl stands in an enviably erect ballet pose, while her no less posturally accomplished mother sits ramrod straight, her toned legs rhyming with her daughter’s. It is an accomplished performance of image projection, pendant to those earlier Dijkstra images of gauche kids in their swimwear, not yet in control of what they disclose to the photographer.

Dijkstra has long studied how we disclose ourselves and how we attempt to control what we announce to the world. And so her art creates powerful tension between what the subject (or their parents) want and what we can do as viewers to subvert image control, to read between the lines, as it were, of their non-disclosure agreements.

In these rooms I came to loathe the parade of the decorous children of the wealthy in their posh frocks and pristine hair. Only one image beguiled me. A boy and girl sit sun-dappled in Liverpool’s Sefton Park, he barefoot and proto-manspreading in his school uniform, she staring us down through black goth fringe, hands folded protectively over her thighs. How lovely to see these human beings, both as hard as nails and as fragile as pressed flowers, in contrast to all the poised poshos desperately finessing their self-images.

There was another treat. Dijkstra’s first British show since 2010 includes an engaging three-screen installation of viewers looking at Rembrandt’s ‘The Night Watch’. Visitors have to imagine that the painting is over our shoulders as different groups — Japanese diplomats, Dutch businessmen, ladies out on a birthday excursion, girls on a school trip — discuss what they see. Rembrandt’s painting is absent so you have to reconstruct it in your head. ‘He looks an aggressive prick,’ says a businessman of ‘The Night Watch’s leader. One girl wonders if you had to pay to appear in the painting. ‘I would only pay if I was in the front,’ she says. Quite so: a portrait announces the subject to the world; nobody wants to be stuck for eternity behind some bewhiskered dignitary in fancy dress.

To reacquaint myself with Rembrandt, I cycled on to the newly reopened National Gallery. As at Marian Goodman, I had to book in advance. This is a very odd experience: after queuing you have to choose between three curated one-way routes through the collection. Social distancing means that at least this is not as bleak an experience as the one I had at the Rembrandt retrospective in the gallery’s Sainsbury Wing years ago, shuffling from one picture to the next as if I was on an art-world chain gang.

Route A is mostly Italian, route B Flemish and Dutch, C German and British. Route B took me to what I wanted to see: Rembrandt’s self-portrait, aged 34. Before Photoshop and Instagram, he fiddled with his image until he was happy, changing the colour of the collar, the shape of the shirtfront, and altering the proportions of light and dark under the face. I looked closely to see the hairs on the back of his neck evoked by scratching wet paint with the end of his brush. Rembrandt was controlling what he let us see of himself, if not sanitising his self-image.