UV – Van Gogh’s friend

• Science
• Lower Secondary (Key Stage 3)

Introductie

Masterminds & Masterpieces – an interactive lesson with an experiment to help students discover how a conservator-restorer uses UV light to examine Vincent van Gogh’s paintings. This lesson also includes instructions for making a UV light. Students can carry out this lesson independently. (Age 12 <)

Instructies

General learning objectives

• Students find out what UV light is;

• Students learn about Vincent van Gogh;

• Students see how conservator-restorers use UV light to examine works of art;

• Students learn how to make a UV light;

• Students discover what fluorescence is and which materials fluoresce;

• Students use UV to examine overpainting in their own work.

A curious, inquisitive attitude is required for the conservation and management of art and also for science and technology in general. This lesson is part of the Masterminds & Masterpieces series and makes use of the cross-curricular added value of inquiry-based learning (experimenting, trying out, looking, comparing, etc.). Masterminds & Masterpieces is a collaboration between the Van Gogh Museum and ASML.

Connection to the curriculum

- This lesson is connected to the subjects Physics and Science.

Materials required for the experiment

- heavy-duty drawing or painting paper (not copy paper, which already contains UV ink, so the experiment won’t work)

- colouring pencils (not watercolour pencils or markers)

- UV ink (to dilute: 2 parts of water to 1 part ink)

- brushes

- acrylic paints

- a UV light, DIY or readymade (365nm)

When using the UV light, you need to have a room that’s as dark as possible.

Students are warned during the lesson never to shine UV light, or any other kind of light, into their own or other people’s eyes.

Materials required to make the UV light

- sticky tape, scissors, rulers

- per student:

 - ice-lolly stick

 - two strips of self-adhesive copper tape (10 cm)

 - UV LED lightbulb

 - battery (button cell)

 - foldback clip

Variations

- This lesson can be taught in conjunction with the lesson UV – Van Gogh’s enemy?

- Students can build their own UV light, but can also work with a readymade one.

- The various parts of the lesson can be used as separate assignments, spread out over a number of moments during the day or week.

Instructies

UV-LED EN.pdf

UV light in the examination and conservation of Van Gogh’s paintings  

UV – Van Gogh’s friend?

What will you learn in this lesson?

During this lesson, you’ll learn what UV light is, what a conservator-restorer does and who Vincent van Gogh was. Then you’ll see how UV helps a conservator-restorer to examine Vincent’s work. Finally, you will build your own UV light, discover what fluorescence is and carry out an experiment. 

What’s happening here?

A conservator-restorer is using UV light to examine Vincent’s painting Sprig of Flowering Almond in a Glass.

What is this person’s job?

This person is a conservator-restorer. She examines and takes care of works of art and old objects, repairing any damage. In this case, it’s a painting by Vincent.

One of the tasks of museums is to study their collections and to preserve them for the future. A conservator-restorer plays an important part in this work.

Conservator-restorer?

The conservator-restorer is a sort of doctor for paintings, who examines the condition of a painting. Is it damaged? Showing signs of age? Does it require treatment? Sometimes, during the examination, a conservator-restorer will use UV light to discover old repairs or overpainting. A good conservator-restorer never just paints something extra. This one’s not very good, then...

What is UV light?

Ultraviolet (also known as UV, ultraviolet radiation, or UV light) is a part of the sunlight that is invisible to the human eye. As UV light has a shorter wavelength (between 100 and 400 nanometres) than visible light, it is more energetic. This means that excessive exposure to this radiation can be harmful to human beings, but also to people. UV radiation is invisible, but you can detect it with your skin. This is because UV makes your skin change colour.

Who was Vincent van Gogh?

- lived from 1853 to 1890;

- grew up in the Netherlands;

- lived in four countries (Netherlands, England, Belgium and France);

- decided to become an artist at the age of 27;

- made almost 900 paintings, lots of drawings and wrote hundreds of letters;

- was not famous during his own lifetime;

- is now a very well-known artist. In 1990, someone paid 82.5 million dollars for one of his works.

Almond sprig

In the first two slides, Vincent’s painting Sprig of Flowering Almond in a Glass is examined. Vincent painted it when he had just moved to Arles, in the south of France.

On 2 March 1888, he wrote to his brother Theo: ‘There’s a hard frost here, and out in the country there’s still snow — I have a study of a whitened landscape with the town in the background. And then 2 little studies of a branch of an almond tree that’s already in flower despite everything.’

How does UV light help the conservator-restorer to carry out the examination? They can use it to…

Meerdere antwoorden mogelijk

1. check the cleaning work
2. seal up cracks in the paint
3. touch up the colour in Vincent’s work
4. discover overpainting

Have you been paying attention? Drag the pictures to the right boxes. 

Before the restoration work

After the restoration work

Experiment: UV – 

a friend?

Find the overpainting in your art.  

Build your own UV light (or buy one) and do the experiment. 

circuit

Your UV research light works because of a circuit.

Do you know how a circuit works?

Here’s a very good explanation.

What shouldn’t you do with your UV light?

Shine it into your eyes – or into anyone else’s. 

Steps 1 and 2

Steps 3, 4 and 5

Build your own UV light

Follow the five steps in the hotspots and make your own UV light. If you already have a UV light, move on to the next slide.

Dit heb je nodig:

You can do this experiment alone or with a partner.

demonstration

Go to the next slide for a demonstration of the experiment.

What do you need?

• heavy-duty drawing paper (not printing paper, because that’s already been treated with UV)
• colouring pencils (not watercolour pencils or markers)
• UV ink (to dilute: 2 parts water to 1 part ink)
• brushes
• acrylic paint
• a UV light (DIY or readymade, 365nm wavelength)

Experiment: UV – a friend?

In this experiment, we’ll investigate what a conservator-restorer sees under UV light.

Dit heb je nodig:

• Take your art and a UV light into a dark area, e.g. a closet.
• Shine your UV light onto the paper. Take a good look to see what you notice and then move on to the next slide for the questions.

3

Steps:

• Do a drawing with colouring pencils (mainly light colours).
• Apply a layer of UV ink (can be diluted) over half of your drawing.
• Let it dry.

If you’re working with a partner, swap drawings. 

1

• Have you swapped? Now paint a few extra things at different spots in the picture. Colour something in or paint something new. Make sure that the changes aren’t too obvious and that your partner doesn’t see you making them.
• Let the paint dry.

If you’re working with a partner, swap again. You should have your own work back now – with a few extras.

2

Wordweb

Use this wordweb to write down your questions and everything you noticed.

What did you notice? And what questions do you have?

Compare your results and Inssaf’s. Write down your conclusions.

Possible conclusions

• Under UV light you can see the new sections that have been added.
• These new additions and overpainting look black under UV light (even though the colour looks completely different in ordinary light).
• The paint doesn’t fluoresce (but the UV ink does!). That’s why you can see the overpainting on top of the layer of ink so clearly.
• You may be able to see some overpainting with the naked eye, but you can see it much more clearly under UV light.

Some things fluoresce under UV light. Use your UV light to find out what other things fluoresce.

Fluorescence?

Fluorescence happens when certain substances absorb light or other electromagnetic radiation and then emit it. Each substance does this to a different degree.

For example, ASML, the manufacturers of computer-chip-making machines, use UV light in their lithography machines. These machines are a part of the chip-production process. UV light makes it possible to produce extremely thin lines (less than 10 nm) on the chip. The thinner the lines, the more will fit on the chip, and the faster and more powerful the chip inside your telephone or tablet will be. 

UV light is used in sunbeds to help people tan faster.

And the police use UV light to detect blood and for other purposes.

Did you know…

that UV light has many different uses?

Now that you’ve finished this lesson, you know:

• what UV light is;
• who Vincent van Gogh was;
• how a conservator-restorer uses UV to study works of art;
• how to build a UV light;
• what fluorescence is and which materials fluoresce;
• how you can use UV light to discover overpainting in your own work.