Demonstration of use of computers in art

Fred Howett

The evening was split into two parts. The first part, up to the tea break, covered use of computers in art related guild activities, and the second part presented an insight into the operation of colour vision

Fred started the evening by stating that this was not a demonstration of drawing and painting directly with a computer or tablet (as recently popularised by David Hockney), but how computers were used to modify photographs of artworks in order to support the different guild activities.

Although word processors and spreadheets are used extensively in the support of the guild's activities they are outside the scope of this demonstration. Instead the focus will be on Image Editors, Desktop Publishing software, and Webpage Editors.

The Image Editor

For this demonstration some of the capabilities of an image editor are demonstrated - in this instance using Serif Photoplus version X2.

Firstly the crop feature is used to select the wanted area of an image. Fred usually takes photos of his paintings by laying them on the ground in daylight but avoiding direct sunlight and photographing them from above ,making sure that the whole painting is captured. The unwanted edges are then cropped off using the image editor.


The images taken by modern digital cameras are of excellent quality and high definition. This is appropriate for applications such as high quality printing of posters, calendars etc, but is excessive for use on websites. This can result in excessive scrolling on a webpage and increased loading times for the webpage. It is normal to reduce the image size for webpage useage.

This is simple to do in an image editor by selecting the Image Size function from the menu, and redefining the required image size in either pixcels, inches or centimetres. For example in the gallery section of the guild website, the thumbnail images of each painting are all 125 pixcels high. The larger images of each painting are 300 pixcels high for landscape mode and 400 pixcels high for portrait mode. For comparison the camera image size of the above painting is 4320 pixcels wide.

Another extremely useful feature of an image editor is the ability to correct the geometry of an image.

When taking photos of visiting artists demonstrations the photos are usually taken from below and to one side of the artist resulting in a distorted image of the artwork as shown below.

Within the Photoplus image editor is a feature called Mesh Warp. With this tool it is possible to drag the corners of the image to restore the original shape.

This is then cropped to produce the final image for the website.

It is also possible to 'paint' on to an image using a brush tool provided within the image editor.

This photograph of a member's painting was scanned into the computer from a photographic print which unfortunately contained a bright red date stamp in the bottom right hand corner. This can easily be removed using the brush tool.


A useful feature in Photoplus is the 'colour pickup' tool. This enables the brush to paint a colour picked up from anywhere within the image. In this case the pavement colour adjacent to the unwanted date stamp is picked up and the date overpainted. This is then repeated with the darker line colour as in the before and after close-ups above.

Although this is a simple example carried out during the demonstration it is possible to use this tool to great effect as shown in the images below. In this example, the unwanted people are removed from the image to great effect.


It is possible to use the computer mouse to perform all the functions of the image editor, but if using the software regularly it may be easier to use a graphics tablet as shown on the left, particularly for drawing and painting functions. However for all the above demonstrations a standard computer mouse was used.


Using the image editor it is possible to turn colour images into black and white images.


Another interesting effect is the colour negative. This was used on the image of a Christmas card design and produced a very different but equally useable image. Two designs for the price of one! Run the cursor over the image below to see the effect.

Another useful tool is the ability to change the tone and the contrast as shown below. The left hand image is the original, whereas the right hand image has had the contrast increased and the brightness decreased.


It is possible to add various shapes in different colours and sizes. Here a white star has been added. One of the most useful features is the ability to add text. This can be of any colour, and any size, and of any font style you have stored on your computer.

Another example of the use of an image editor is shown below in the design for a specific birthday card. The final image size was for a 7 x 5 inch photoprint. The original aircraft image only extended to the vertical line. The sky area to the right was added as a rectangular shape, the colour of which was picked up from the sky of the original image. The smoke trails were extended by means of the brush tool using the colour picker to match the colour of the original smoke. Finally the text was added, again picking up the colour of the aircraft. The printed image was then glued to a blank card. Note: the blue rectangle is only there to pad the image out to 7x5 inches.

The Desktop Publisher

The Dektop Publisher software is like a supercharged word processor. It provides almost limitless flexibility for positioning text and images on the document. It can provide outputs of enormous variations in size, and provides output formats sitable for commercial printing organisations. The artwork for all of the guild exhibition posters and preview invitations since we introduced colour in 2009 have been generated using the Serif Pageplus desktop publishing software. As have our recruitment posters, guild membership cards, and banners right up to five metres in length.

To demonstrate the use of desktop publishing software we will look at the most recently created poster, for an exhibition of three water colour artists work at the Reel Cinema Gallery in Borehamwood. The original sketch for the design is shown below. A watercolour wash was added at the top of the paper and allowed to run down to create a dynamic effect. When dry, the brush was added then photographed as was the tube of paint.



These images were transferred to the computer and imported into the desktop publisher. The different blocks of text were then added to complete the design. The printing rquirements such as crop marks and registration marks were then added and the document then exported as a pdf file ready for printing as shown below.

The webpage Editor

This is the equivalent of a word processor for producing pages for displaying on websites. It uses a special language which is common to all website browsers.

For this demonstration some photos were taken in the studio during the demonstration. These were transferred to the computer and two images selected, reduced in size by the image editor, then incorporated into a simple web-page using the webpage editor. This was then uploaded to the internet from the studio and was checked by members using their smartphones.


Finally the following three questions were posed, for members to consider during the tea-break.