I thought I would give a brief history of the technique first.
It is not a new technique-reverse painting on glass has been around since the medieval times. Some sources say it began in the Renaissance in Italy on the Island of Murano, but Wikipaedia says it started earlier than that -around Medieval times.
It was widely used for sacred paintings and Religious iconography since the Middle Ages. The most famous was the art of icons in the Byzantine Empire. Later painting on glass spread to Italy where in Venice it was influenced its Renaissance art. Since the middle of the 18th century, painting on glass became favoured by the Church and the nobility throughout Central Europe.
The painting can be realistic or abstract, but is generally seen to be used as a naive form of art popular in Germany, Romania, Russia and Poland.
This process is not like stained or leaded glass work in that it is not intended to hang in a window with light coming through the piece. Hanging on a wall, framed or unframed, with a lot of light directed towards the piece provides best viewing.
I learnt this technique with Paul Birchall who showed me how to use Plexiglass or perspex- it is a "friendlier" medium than glass- less apt to shatter!
The basic principle of the technique is that everything is reversed. The painting is done on one side of the perspex. The lighter colours are applied first, which is the opposite of oil-painting technique where one works from dark to light and any highlights are placed at the end. In reverse painting the opposite is true- one puts the highlights in first.
Each layer of colour is applied over the previous layer, so that the final result is a composit. For instance if you put yellow down first, then red over that, the final result will be an orangey colour. So you are getting a mixed result. It is best to apply the lighter colours first as you cannot lighten them later. Remember you are basically painting on the "back" of the perspex. You have to turn it over to see the result on the "right" side.
However all is not lost if you do decide to lighten up later- you simply scrape away the layers and add your lighter colours in then. More labour intensive perhaps but you can get some interesting results.
Mmmm- this sounds a bit like ageing, doesn't it? We simply discard all the baggage we have accumulated over our lives and lighten up hey!
Workshop went quite well. About 20 people came and seemed to enjoy it.
This was the painting which I did