BWTAS is British in name but not in its outlook. In the Moorish* town of Tavira in the Algarve, Portugal, there is a delightful camera obscura housed in a redundant 1931 concrete water tower. The Torre de Tavira was founded in 2004 by English astronomer Clive Jackson and his wife Gloria who also run astronomy holidays from their observatory in the Algarve.
Looking over the tower from a construction viewpoint, it seems to be typical of the Mouchel pattern with an Intze floor. There are many water towers in the Algarve region. Like the famous variety of Algarve chimneys, some have Moorish influences in their detailing but most of the larger municipal towers such as at Portimao are fairly basic as they were built during the economic hardships of the Salazar era.
The Torre de Tavira occupies a prominent position at the top of the town and is right next door to the Igreja de Santa Maria and the town's castle, all are popular tourist destinations.
So what is a Camera Obscura?
When inside the darkened room (the former tank) a rotating mirror in the roof projects the view of the town onto a dished table whilst the guide gives a narrated tour. The view is telescopic, bringing sights far away into view, but it also has a wide field of view as the image is projected large onto the table with incredible precision, like a super high-definition screen.The effect of seeing very distant people, cars, trains and boats moving with such clarity is truly amazing.
For this reason, camera obscuras were very popular in pre-television times. Britain still has several although many have been lost and there is one in the Foredown Tower in Brighton which is situated in a..... yes, a former water tower.
If you plan to visit this tower, try not to confuse it with the Torre Tavira in Cadiz, Spain which is also a great camera obscura too but is NOT in a converted water tower. The tower, in the Baroque style, was part of the Palace of the Marquis of Recano whose first watchman, Antonio Tavira, gave it its name.
Some BWTAS members think there are a number of sites in the UK where concrete or metal water towers are ripe for this kind of conversion. The Jacksons have submitted plans for an astronomy 'Astrotel'. Seeing how well the camera obscura has been done, we wish them every success.
Thanks again to David Blackburn for his image.