The first issue was how to mount it in front of the lens. I've seen blog posts where some people have taped the glass to a screw-on UV filter. This means you can only use it for lenses of the same size as the filter. Another option was to use a tulip lens hood reversed and hold the welding glass in place with rubber bands. This will work for any size lens providing it has a tulip lens hood. I had a flat lens hood that fits onto my EFS 18-55mm zoom via a bayonet mount, rather than the filter screw-in. so I taped the glass to the lens hood with electrical tape. It mounts and unmounts easily with a quick twist.
|Lens hood taped to welding glass|
|Attached to the lens|
|In place and shooting!|
Also welding glass is really dark (that's the whole point, isn't it?) and it's impossible to focus with the filter in place. So you have to focus with the filter off and then attach the filter. In my case this means twisting the lens hood into place which means messing up the focus. By trial and error I learned to remember where the lens was focused and return it as close as possible to that position once the filter was in place.
The result is worth the effort however. I was able to take very long exposures of two to five minutes in the afternoon (albeit) on a cloudy day. Here are a few of my better results from taking photos of traffic on State Street near my home during rush hour traffic.
|F/8 1/125-second Exposure|
|F/5.6 Two-minute Exposure|
|F/11 1/200-second Exposure|
|F/5.6 130-second Exposure|
|F/5.6 100-second exposure|
Can't wait to try this out on someplace other than a busy road. Perhaps the BYU campus during class break? Or some moving water shots like the Provo River or Bridal Veil Falls.