Plein air sketchbook

Credit: Cally Lawson

If you’re venturing outside of your studio for the first time and need some advice on watercolour plein air painting, this helpful guide contains a range of top tips on what supplies to take and more.

What is plein air painting?

En plein air (in the open air) refers to the act of painting outdoors. Discover more art terms in our handy online glossary

Plein air painting supplies – watercolour

Painting plein air supplies

Everything I need for painting outdoors: a board, which fits into the A3 folder along with my paper. My rucksack and contents, which includes painting palette, brushes, pencil, pipette, tubes of paint, masking tape, water pots and bottle. Also shown is the easel and shelf in its folded state, which I keep together with two bungees. When I’m on the move, I have the rucksack on my back, my A3 folio over my shoulder and I carry my easel with a free hand - David Webb.

Watercolour paper

The first thing to consider is the size of the paintings you want to produce outdoors. Will they be in a sketchbook, which can be small and packed in the rucksack, or do you want to paint larger scale?

It's good to standardise your outdoor painting kit, and this includes the size of the watercolour paper.

Cutting down full-size Imperial sheets (22x30in.) into quarters means you can paint four pictures from a full sheet, and you carry less.

Top Tip - Taking a couple of stout polythene bags for paper and paintings guarantees that the contents will be protected from any unforeseen downpours.


Painting en plein air

When painting in a sketchbook I use this very small set of half-pan paints. Notice the brush handle has been shortened to allow it fit inside a jacket pocket

David Webb recommends using a small enamel tin of half pans for plein air sketchbook work.
For the quarer-Imperial paintings, he uses a plastic palette with a hinged lid which has space for 12 colours and five large mixing wells.

Watercolour brushes

David Webb prefers using large, squirrel mops to sables. It’s a matter of personal choice but, whatever type of brush you prefer to use, you only need to take two or three. 


It's worth taking a few pencils, along with a craft knife for sharpening them. Remember that watercolour paper is soft so it’s best to steer away from the harder grades of pencil when drawing, go for something like a 3B.


Apart from the paints themselves, the other main ingredient for watercolour painting is the water itself. Unfortunately, water is heavy so don't try to carry more than a litre.

If you’re painting in town then it’s not much of a problem finding water. If you’re painting near a river, you can always top up there, too.

When not readily available, use your supply wisely. Don’t pour it all out at once, as it will become dirty quite quickly when you rinse your brushes. It’s better to ration it; if you accidentally kick it over, you always have more.


David Webb painting plein air on an easel

Painters usually fall into two categories. There are those who like to stand and those who prefer to sit. If you stand, you’ll need an easel.

When setting up an easel, it's a good idea to place a small spirit level on the tray and adjust the legs until it is level. This means that, when you mix up washes of colour, they stay in the middle of the wells and do not slop over the sides.

One of the drawbacks of using an easel outside is the unexpected gust of wind, which can send it toppling over along with the paints and water. To prevent this, you can suspend your rucksack from the centre of the easel, with a couple of bungees.

Example of a plein air painting

Watercolour Sketch on 140lb Bockingford NOT, (28x38cm)

This is a typical outdoor painting, created with the equipment described above. Details, like location and date, can be written on the side, which will be hidden by the mount when the picture is framed.

Top tips for en plein air painting

Now you know what equipment to take with you, John Somerscales and Linda Matthews share their advice for painting en plein air.

  • When you find a view that interests and inspires you, go for it! Don't be tempted to see what's round the next corner, you could end up walking miles and getting so tired and frustrated that you lose the appetite to do anything.
  • On a sunny day, try to position yourself so that you are in the shade to avoid glare from the white paper. If this isn't possible sunglasses are an option, but remember that you'll need to keep them on throughout the painting process.
  • Use a card viewfinder to isolate your composition and decide on the format: landscape, portrait or square.
  • Squinting through half-closed eyes will simplify scenes and enhance the tonal range.
  • If possible, divide your palette into warm and cool colours. This makes mixing more logical and effective.
  • The option of standing at an easel gives you the advantage of a higher viewpoint – useful for looking over low walls, for example.
  • To encourage a freer, looser style, set yourself a time limit of (say) one hour. The shadows and light will probably have changed in this amount of time anyway.
  • Early morning and late afternoon provide the more interesting light effects. Avoid midday when the sun is at its highest. Try working contre-jour (into the light): this simplifies detail and makes for a more dramatic atmosphere.
  • When you have settled on your view, concentrate on first painting the elements that might change: figures, boats, cars, shadows etc. Buildings and trees will not move.

Get more plein air painting advice from John as he demonstrates a painting of Dunster Castle.

Plein air painting tips from Linda Matthews

  • Keep a list of all the equipment you need so you don't forget anything important.
  • Make sure you have your lunch and drinks with you.
  • Keep a set of equipment in the boot of the car; it’s great for when you feel unexpectedly inspired.
  • Pack a hat for hot (or cold) weather and wear layers.
  • Make a quick pencil sketch of your subject, noting tonal variations, colours, feelings and shadows. This is just in case you have to abandon your work due to weather.
  • Take a photograph for colour reference, not to copy.
  • If working in bright sunshine, look at your highlights in domestic light when returning home. You may find they don't look as light as you thought.

Now you’re ready to start painting en plein air, check out this guide from Alan Bickley for how you can scale-up your plein air sketch once you’re back in the Studio.