Using welding glass as a cheap filter
08th January 2012
The weather looked good to try to get some long exposure shots of moving clouds and water using welding glass as a filter. I've read several articles in photo magazines and on the internet on using pieces of welding glass as a filter to take long exposure shots. The theory is is that the glass acts like a very strong pair of sunglasses (when you look through it you can hardly see anything). When placed in front of a lens it means you need exposure times of more than 20-30 seconds to get a correctly exposed photograph. The long exposure results in any movement, such as clouds or water, to have a dream like blur. To keep other areas in sharp focus requires the camera to be mounted on a tripod
Whilst the welding glass is not of optical quality and results in a photo with a heavy green of purple colour cast, at around £3 a piece, it is significantly cheaper than a professional filter which will set you back £80-100. The drawbacks are the quality of the picture (though not too bad) and the colour cast. The latter can be removed by editing in Photoshop and removed totally if converted to a B&W print.
So, having used a bit of gaffer tape to attach the welding glass to a filter mount used for mounting a square filter bracket to my Sigma 10-20mm wide angle lens, I made may way off to the Paull Nature Reserve - the aim being to grab a picture of the moving clouds above the moving water on the mud flats. The problem was the weather. By the time I'd arrived there were a lot more clouds and much less sunlight. I spent the next 1-2 hours taking pictures of the mud flats and the migrating birds, waiting for fleeting moments for breaks in the clouds.
Before leaving I thought I should at least try the welding glass technique - given that this was what I had set out to do. I did grab one or two pictures. Whilst, compositionally, they are not the best of photographs, they at least prove the technique works.
To see some of the other pictures taken (without the welding glass) go to the "Water" gallery.
As shot image - notice the heavy green tint due to the welding glass. Picture is also underexposed for the land, though about right for the sky. I should have taken two shots - one exposed for the sky and one for the land.
Final edited picture. Converting to B&W has removed the green colour cast. Also, by selectively adjusting the exposure of different areas of the photo I've managed to create a more balance picture. Finally I added some digital noise to give a grain effect and a vignette, to give the picture more of an old B&W print effect.
Whilst the welding glass is not of optical quality and results in a photo with a heavy green of purple colour cast, at around £3 a piece, it is significantly cheaper than a professional filter which will set you back £80-100. The drawbacks are the quality of the picture (though not too bad) and the colour cast. The latter can be removed by editing in Photoshop and removed totally if converted to a B&W print.
So, having used a bit of gaffer tape to attach the welding glass to a filter mount used for mounting a square filter bracket to my Sigma 10-20mm wide angle lens, I made may way off to the Paull Nature Reserve - the aim being to grab a picture of the moving clouds above the moving water on the mud flats. The problem was the weather. By the time I'd arrived there were a lot more clouds and much less sunlight. I spent the next 1-2 hours taking pictures of the mud flats and the migrating birds, waiting for fleeting moments for breaks in the clouds.
Before leaving I thought I should at least try the welding glass technique - given that this was what I had set out to do. I did grab one or two pictures. Whilst, compositionally, they are not the best of photographs, they at least prove the technique works.
To see some of the other pictures taken (without the welding glass) go to the "Water" gallery.
As shot image - notice the heavy green tint due to the welding glass. Picture is also underexposed for the land, though about right for the sky. I should have taken two shots - one exposed for the sky and one for the land.
Final edited picture. Converting to B&W has removed the green colour cast. Also, by selectively adjusting the exposure of different areas of the photo I've managed to create a more balance picture. Finally I added some digital noise to give a grain effect and a vignette, to give the picture more of an old B&W print effect.
