After completing our technical examination of the painting, taking lots of pre-treatment photographs and writing the condition report, we write a treatment proposal for the painting. We consider the current condition of the painting and what we would like to achieve with different treatments. Our proposal is discussed with the curator and together we outline the aims and objectives of the treatment. No cleaning of a painting is without risk so all options need to be discussed.
The treatment schedule for Poedua begins with surface cleaning the reverse of the painting. Methods of surface cleaning fall into one of two categories; Dry, where brushes, tweezers, erasers and/or sponges are used to lift and remove surface dirt from the surface; or Wet, where aqueous solutions, solvents or gels are used to lift and remove the surface dirt. Generally for paintings on canvas we begin with cleaning the reverse of the painting using dry surface cleaning methods.
For Poedua the cleaning of the reverse of the canvas occurred in a number of stages. It began all the way back in November when the painting was still in London. To prepare the painting for travel, dust and debris were removed from the area between the canvas and the bottom stretcher member. This was removed because the pieces could have moved around during transit and caused damage.
Forward a few months and the painting is in the conservation lab. We carefully lay the painting face down onto a clean table and use a brush and an indirect vacuum (holding a vacuum on low power above the canvas rather than touching the canvas with the vacuum) to remove the loose dust and dirt particles.
This was only partly successful so we cleaned further using small pieces of dry cleaning sponge to lift dirt that was caught in the interstices of the canvas weave.
Finally we removed more dust and debris which was caught between the canvas and the bottom stretcher member. It was impossible to complete this part of the treatment in London because of the restrictions of materials, time and place. We held the painting up at the bottom edge and left the top edge resting on the table to allow the dust and debris to fall away from the painting. We used a variety of tools to carefully remove as much as possible from this area.
Our treatment of surface cleaning the reverse of the canvas has resulted in the inscription being clearer and easier to read.