MoMA Assistant Conservator Jennifer Hickey inspects the paint surface of One: Number 31, 1950 under magnification

In our last post, we took a closer look at the variety of visual effects Pollock was able to achieve with his painting technique. We also observed some passages of paint that don’t appear to fit the typical characteristics of poured house paint. So we set out to investigate this seeming inconsistency.

Looking at the “different” passages on One, we observed that they shared similar qualities. The color, texture, and style of application appeared to be consistent from one to the next. We considered the possibility that these areas of paint were added in a single campaign, later (after Pollock painted it in 1950) by a conservator or restorer or even possibly by Pollock himself. To determine whether or not this was the case, though, we needed to collect as much information about the painting as possible and interpret that evidence.

We approached the question on two fronts. The first was to examine the painting closely employing a range of analytical tools commonly used by conservators. The other front was a search for a paper trail, either a written record of conservation or a photographic record that might clarify whether the painting had been restored in the past. One’s conservation file, however, contains no record of treatment by the Museum’s conservators indicating that any treatment would have occurred before the Museum acquired the painting in 1968.

Areas inconsistent with Pollock’s painting technique are found scattered across the painting. These regions share similar qualities in their color, texture, and style of application

Areas inconsistent with Pollock’s painting technique are found scattered across the painting. These regions share similar qualities in their color, texture, and style of application

Areas inconsistent with Pollock’s painting technique are found scattered across the painting. These regions share similar qualities in their color, texture, and style of application

Areas inconsistent with Pollock’s painting technique are found scattered across the painting. These regions share similar qualities in their color, texture, and style of application

We found support for this in correspondence that alludes to a restoration campaign sometime in the mid-1960s, but no documents clarified exactly why the painting had been restored or what had been done to restore it. We pored over archival images, but photos taken at a distance to capture the nearly 18-foot work inevitably lacked the small-scale specificity we needed to compare palm-sized spots of paint.

A 1958 installation view of One at the Galleria Nazionale d’Arte Moderna in Rome provides a useful reference for the painting’s general condition at the time

Cropped detail of One’s lower right corner from the 1958 image. As you can see, trying to obtain detailed information from such photographs, however, proves to be limited

What we needed was a detail photo and not just any detail: a shot framed to correspond to one of our areas of interest and with sufficient resolution to properly assess any changes that might have occurred. To our great fortune, the “money shot” materialized. We located a detail photograph dating to 1962 and taken by a scholar (Charles Rhyne, an art historian at Reed College) in Portland, Oregon, when the painting was exhibited as part of the traveling exhibition organized by MoMA, The Collection of Mr. and Mrs. Ben Heller.

A detail of One’s lower right corner as it appeared in 1962

The same region of the painting as it is today

A comparison to the same area of One as it appears today definitively reveals that the “different” paint is in fact sitting on top of original paint.

Details, circled in red, of the 1962 photograph

Details, circled in red, of the painting today. Notice the differences in the paint layer, circled in red, between the 1962 and 2013 images. The cracking observed in 1962 is no longer visible, and the composition, color and texture of the paint has changed

Here, a detail of the upper red circle (from the 2013 image above) shows how paint covers and fills cracks in the underlying original paint 

Now, as Pollock had died in the summer of 1956, our 1962 photograph rules out the possibility that this paint had been applied by the artist or in consultation with him.

It is demonstrably overpaint, applied during a restoration campaign.

But this clarification still leaves us with points to consider. Presumably, the overpaint was applied by a conservator to mask areas of damage, but what is the nature of the damage? Moreover, what is the nature of this overpaint? How can we distinguish, with certainty beyond the visual evidence, overpaint from original Pollock paint? Can the overpaint be safely removed, and, if so, what are the arguments for and against removing it?

It’s common for conservators to obscure spots of damage on a painting by applying their own paint. This is typically called retouching or inpainting and is limited to areas where original paint is missing. Applying paint over original paint is distinguished from this more restrained practice and is called overpaint. Early restorers (during the 19th and early 20th centuries) tended not to worry about differentiating their materials from the artist’s original. For example, oil paintings were often retouched and overpainted using more oil paint, a combination that becomes very difficult to separate as it ages. As art conservation grew during the mid-20th century into a profession with stated theoretical aims and ethical standards, however, conservators agreed that any paint applied—say, to cover a loss or disguise cracks—should be easily reversible, that is, removable without disturbing the original surface. In addition such retouching should not cover original, undamaged paint.

In our next post we will follow our second line of inquiry about these passages of paint, now clearly established as overpaint, to discover more about what their material composition in fact is. This will be essential in guiding our decisions about whether we should remove them and, if we do, how best to do so.