UV - Van Gogh's enemy

• Design and technology
• Art and design
• +1
• Primary Education
• Lower Secondary (Key Stage 3)

Introductie

Masterminds & Masterpieces – Using two of your own drawings, you’ll carry out an experiment to show the influence of UV light on works of art. Note: You’ll need at least a couple of weeks to complete this experiment. The lesson involves two parts – and a lot of patience. (Age 10 - 12)

Instructies

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.

Time indication

This lesson consists of two parts. The first part (around 45 min.) focuses on preparation for the experiment. In the second part (around 30 min.), the results are viewed and discussed. Please note that there need to be at least two weeks between the two parts of the lesson.

Materials

For each student:

• 2 sheets of heavy-duty drawing paper
• a sheet of thick paper or card (size: 1/2 of your drawing paper)
• drawing pencil and felt-tip pens in at least 5 colours
• paperclips
• sunscreen spray
• old newspapers
• optional: writing paper or tablet

The lesson can also be done in pairs.

Extra preparation

If the students aren’t quite sure who Vincent van Gogh was, watch the video Who Was Van Gogh?

Variations

- This lesson can follow on from the lessons UV – Van Gogh’s friend (parts 1 and 2).

- The first part can be shortened by not asking the students to do a picture but instead to use a ruler and felt-tip pens to draw a number of lines in different colours on the paper.

- Would you prefer not to use sunscreen spray? Static and transparent UV resistant window film is a good alternative (online search term: ‘static UV-resistant film’)

- For students who can handle slightly more difficult material, the related lessons for higher-level students can be used.

UV: Van Gogh's enemy

What’s this lesson about?

Prevention is better than cure. In a museum, the staff make sure that the paintings are well protected. But even if everyone is really careful, danger is always lurking. Dust, for example, or damp, or... UV light.

Use the hotspot to discuss the subject of the lesson.

Where do you think we are?

This is a very large microscope. You can use it to look at the picture’s layer of paint from very close up.

What kind of machine is this?

This is the Van Gogh Museum’s conservation studio. This is where paintings are examined and restored. Restoration means repairing something that’s damaged or old.

What is this woman’s job?

This woman is a conservator-restorer. A conservator-restorer examines and repairs things that are damaged or old. In this case, it’s a painting by Vincent van Gogh.

Use the questions in this slide to activate the students’ previous knowledge and to encourage them to look closely at the photograph. The answers are in the hotspots beside each question. If necessary, you can emphasise the words in italics to help students develop their vocabulary.

The conservator-restorers at the Van Gogh Museum are like doctors, but for paintings. These ‘doctors’ examine and repair the paintings when necessary. This means that the paintings are kept in good condition and people can continue to enjoy them in the future.

The hotspot contains a brief explanation of what a conservator-restorer is.

sunlight

Sunlight sends a lot of different colours to us, but we can’t see all of those colours with the naked eye. Like ultraviolet (UV) and infrared. We do see all the colours between them, though.

UV light

If you sit in the sunshine for too long without protection, you’ll get sunburn. It’s because of the UV light in the sun’s rays. They change the colour of your skin. And it’s painful! UV light is also harmful to paintings, but in a different way.

You’ll find an explanation about sunlight and UV light under the hotspots.

Length: 3:41 min.

If the students have already completed the lesson UV – Van Gogh’s friend, they’ll be familiar with the video and this part can be skipped.

Paintings obviously don’t really ‘wilt’ like the one in the picture. Vincent knew that the older his paintings became, the greater the chance that they wouldn’t remain as beautiful. He compared this to flowers fading. Those were his own words.

Have a brief discussion of the video and the cartoon afterwards.

Experiment

What does UV light do to your drawing?

Tell the students that they’re now going to see the influence of UV light on art for themselves. The following slides contain the instructions, including a demonstration video.

This is what you need:

• 2 sheets of heavy-duty drawing paper

• a sheet of thick paper or card (size: 1/2 of your drawing paper)

• drawing pencil and felt-tip pens in at least 5 colours

• paperclips

• sunscreen spray

• old newspapers

Watch the demonstration

What are you going to do?

1. Make two drawings and colour them in with the pens.

You can also just trace over the pencil lines with colour, or draw with the pens straightaway.

Use lots and lots of colour.

Lines instead of drawings

Instead of drawing a picture, you can just draw horizontal lines. Use a ruler and pens in as many different colours as possible. Do this on two sheets of paper.

The alternative exercise with lines can be found in the hotspot with the pencil.

What are you going to do?

2. Cover half of one drawing with heavy-duty paper or card. Secure it with paperclips.

3. Place a sheet of paper over half of your second drawing. Spray sunscreen over the other half.

Give it time to dry.

What are you going to do?

4. Hang the drawings in a window that gets plenty of sun.

And then: be patient...

Wait at least 2 weeks in the summer – and even longer in the autumn, winter or spring!

The differences in duration are connected to the varying intensity of the sunlight throughout the seasons.

What do you think is going to happen?
Which protection do you think will work best?
What differences do you expect to see?

Ask the students to briefly describe their expectations.

Whole class: collect and write the answers on the digital whiteboard. Answers can also be sent to the interactive whiteboard by mobile phone (click on ‘devices in the classroom’ ).

Take a photograph of their predictions, or ask the students to write them down and keep them.

And now it’s time to wait!

Decide when you’re going to take a look at the results of the experiment and put the date in your calendar. Note: Plan at least two weeks ahead, preferably longer.

....weeks later 

What do you see?

Answer these questions

• Do you see any discoloration?
• Is the discoloration equally bad for every colour? Which colour shows most/least discoloration?
• What provides more protection: thick paper or sunscreen? Why do you think that is?
• What would happen if the drawings were to spend longer in the sun?

Write the number of weeks that have passed on the interactive whiteboard. After a brief review, ask the students to study their pictures and then to answer the questions in the hotspot individually or in pairs. (In pairs: also ask them to compare results.)

Group discussion after around 10 minutes.

And..?

Did you see the same results in Inssaf ’s experiment?

What was the same? What was different?

The same experiment can have different results.

Why do you think that is?

Finally, watch the video and then discuss this using the questions in the hotspot.

Allow students to reach the conclusion that different circumstances can lead to different results. For example, using a different brand of marker pens, a different kind of paper, different sunscreen spray, or if the sun’s not as bright or you leave the work for a shorter period of time, etc.