The volcano showed its face in the end - just once, mind you.

Amid a weekend of relentless rain and low, low cloud, the snow-capped cone of Cotopaxi, Ecuador´s most famous volcano, emerged just once.

For almost the whole of our stay at the Secret Garden Cotopaxi, the 5,897m giant sat wreathed in cloud. The volcano´s ¨perfect¨cone was invisible behind the wall of water vapour. Up in the clouds, the rain that fell on the muddy fields around the Secret Garden (altitude: 3,450m) fell as snow. With each hour our chances of a decent walk on Cotopaxi´s 5,000m glacier receded: too much snow meant avalanche risk.

Too much cloud, though, meant something much, much worse - no view to speak of. Considering that the Secret Garden was built on a hand-picked site in view of something like nine snow-capped peaks, too much cloud was a real downer.

I´ve got used to clouds in recent weeks. Since we left the coast of Colombia in late February our journey through the Colombian Andes and into Ecuador has only occasionally been interrupted by bursts of sunshine.

In Popayan, Colombia, clouds obscured a spectacular sunset at the end of what was admittedly a lovely sunny day.

Elsewhere, the story was the same. In San Agustin, close to a fertile and verdant Colombian valley once home to a mysterious pre-colonial civilisation, clouds dulled the view for almost the whole of an otherwise enjoyable horse ride. In Salento, home of the wax palm, Colombia´s national tree, my photos of this soaring giant were set against a backdrop of uniform white.

Quite apart from being irritating and wholly un-exotic, relentless cloud poses a constant challenge for a photographer. Correctly expose the foreground (the interesting bit) and the cloudy sky becomes a searing white mass of over-exposed uselessness. But if you try and keep the sky within the range of the camera´s sensitivity you are forced to under-expose the ground, leaving the bit you really want dark and shadowy. Photo geeks will know that filters can help correct this, but it´s simply impractical to whack on a screw-on filter holder and slot in the ND grads every single time a shot takes your fancy.

Especially when there´s this much cloud around.

So I´ve been learning to work with the weather, which is apparently all the fault of La Nina, El Nino´s evil twin sister, who has dumped record amounts of rain onto South America so far in 2008. (Ask anyone in Ecuador, where the newspapers are full of flood reports and weather-related disasters, and they will tell you the weather so far in 2008 has left them baffled.)

Sometimes, when there´s nothing else to shoot, cloud becomes a crucial and impossible-to-ignore part of a scene. At the Secret Garden Cotopaxi, pictured above, the heaviness of the cloud helped give a sense of the remoteness of the place.

And near the summit of Volcan Ruminahui, after trekking to more than 4,000m for the first time ever, wispy clouds rolling in all around us offered a disorientating glimpse of the storm that was to come and soak us an hour later, as well as a moody and mysterious take on a mountain-top scene.

I´m not going to wax lyrical about clouds - their endless shifting shapes, their subtle colours, the captivating way low clouds can hang below you, meandering their way somewhere, sometime - but I feel like I´m on good terms with them now.

And of course when the clouds part just as the sun goes down, it´s easy to forget the frustrations of another white-off of a day.