What the slide projector knew that we have forgotten.
A long meditation on how 35mm slides shaped the way a generation of artists looked at their own work — and what was lost when we stopped projecting. With apologies to younger readers.

Until roughly 2007, every art school in Britain — and in most of Europe, and in much of North America — kept, somewhere in its premises, a slide library. The slide library was, typically, a small room with metal cabinets along the walls. The cabinets contained 35mm transparencies in card mounts, arranged by artist, by period, or by some idiosyncratic scheme of the institution's own devising. The slides were borrowed by tutors for use in lectures. They were returned, often with delays, in small cardboard boxes. They were occasionally lost. They were, by the standards of the contemporary digital archive, almost laughably inefficient.
The slide library is, now, almost entirely gone. The major art schools digitised their collections in the late 2000s and early 2010s, with varying degrees of care, and the original slides are either in deep storage or — in some cases — have been disposed of. The lecture is now given from a laptop. The image is projected, in full colour at much higher resolution than the slide was ever capable of, onto a screen behind the speaker. The students take notes, increasingly, on their own laptops. The whole transaction is, in technical terms, an unambiguous improvement.
I want to argue, however, that it is also a loss. The loss is not technical. It is closer to a loss of a particular kind of attention.
What the slide did
The 35mm slide, when projected on a screen at the dimensions typical of an art-school lecture hall, presented an image that was — by the standards of how we now see images — markedly imperfect. The colours were slightly off. The image was slightly blurred. The brightness varied with the age of the bulb. The corners of the image were often slightly out of focus. The contrast was — depending on the slide and the screen — sometimes flatter than the original work, sometimes more dramatic.
These imperfections were, however, consistent imperfections. The slide library presented every artwork through the same imperfect medium. A Vermeer was projected with the same colour palette, the same grain, the same approximate level of focus, as a Pollock. The viewer learned, over time, to read past the limitations of the medium. The viewer learned, over time, what the medium could and could not show.
This is, in my experience as both a student and later a tutor, the part that is missing from the contemporary digital projection. The digital image is, by comparison, almost too good. It does not, generally, declare its limitations. It presents itself as a faithful reproduction of the work, and the viewer — particularly the young viewer who has never sat through a slide lecture — has no obvious way of knowing where the limits of the reproduction are.
The slide knew it was a copy. The digital image, increasingly, pretends to be the work itself.
What the lecturer did
The slide-based lecture had a particular rhythm. The slide had to be changed, manually, by the lecturer. Each change of slide took two or three seconds — the click of the carousel, the flash of the lamp, the moment of darkness, the new image settling into focus on the screen. The rhythm of the lecture, by necessity, accommodated this. The lecturer spoke a little, paused, changed the slide, spoke a little more.
The two-or-three-second pause was, in retrospect, the most important pedagogical feature of the slide lecture. It gave the audience time to absorb the previous image before the next one arrived. It gave the lecturer time to think about how to introduce what was coming. It gave the room time to settle. The lecture had, by virtue of the slow medium, a kind of internal pacing that did not need to be managed consciously by the lecturer; the pacing was built into the equipment.
The digital lecture has no such pacing. The slide change is instant. The lecturer can, and frequently does, move from image to image at the pace of speech rather than at the pace of looking. The audience is, in many contemporary lectures, presented with far more images than they can absorb. The pacing is, when it is good, the result of conscious effort on the part of the lecturer. When it is not good — and it is, in my experience as a frequent attender of contemporary lectures, often not good — the audience drowns.
What the artist did
The slide was also, for many artists of the period from the 1970s to the late 1990s, the primary mode in which they encountered their own work after it had left the studio. A painter who had sold a painting at a London show, and who was then giving a talk in Cologne, would carry with them a small box of 35mm transparencies of the work they had been making. The work itself was elsewhere; the slide was the artist's record of it.
This had, again, a particular effect on how artists thought about their own work. The painter who looks at a slide of their own painting is looking at an imperfect reproduction. They can see what the slide preserves and what the slide loses. They have, by necessity, a critical relationship to the image of their own work; they cannot mistake the slide for the work itself.
The contemporary artist, by contrast, often sees their own work primarily through high-resolution digital images. These images are, increasingly, indistinguishable to the casual eye from the work itself. The artist's critical relationship to the reproduction is, in many cases, weaker than it was a generation ago. The artist who has only ever seen their own painting on a Retina display has, in a sense, never seen it.
What this has to do with criticism
The implications for art writing are, I think, real. The art critic of the slide era worked with the assumption that the reproductions in front of them — in slide libraries, in catalogues, in books — were imperfect proxies for the work. The critic was obliged to see the work in person, in the room, in order to write about it with confidence. The reproduction was a memory aid, not a substitute.
The art critic of the digital era is under more pressure to write from the reproduction. The images are too good; the workload is too high; the budget for travel is, for most independent writers, non-existent. The critic who has only seen the work through a high-resolution image is, in many cases, writing as if they have seen the work in the room. The reader has no easy way of knowing the difference.
This is, I want to be careful, not a moral failing on the critic's part. It is a structural condition of the contemporary writing economy. But it is, even so, a real loss, and one that the slide-era critic would have recognised at once.
What I would not advocate
I am not, to be clear, advocating a return to the slide library. The slide library was, in many practical respects, a nightmare. Slides were lost. Slides faded. Slides broke. The whole infrastructure was expensive, fragile, and dependent on a small number of curatorial staff whose work was, in most institutions, chronically under-valued.
What I am advocating is a more conscious relationship, in the contemporary art-writing economy, to the reproductions we work with. The digital image is not — despite appearances — the work. It is a reproduction. Like all reproductions, it shows some things and hides others. The critic, the lecturer, the artist, and the reader all need to remember this, repeatedly, in a way that the slide quietly required us to remember by being so visibly imperfect.
The slide projector, in its slow and limited and frankly inconvenient way, knew it was a projector. The Retina display, in its faithful and high-resolution and beautifully colour-managed way, would prefer that we forgot it was a screen. The forgetting is the loss. The remembering is the work.