Aurora Aperture Power ND Neutral Density Filter Set
I have a really old ultra-wide lens, the Sigma EX DG 15-30mm that I purchased in the early 2000's. This lens is super sharp and nice and I've never seen the reason to ditch it for something else. I actually have made quite a bit of money over the years with this lens doing real estate photography.
One drawback is the inability of the lens to accept filters on the front. Sigma was nice enough to put a clip on the back that accepts Gel's so you can stick those back there, but it's not easy to use.
A company called Aurora Aperture has made a set of ND filters that will work with the Canon branded ultra wide lenses, and I inquired to them if they might be compatible with my Sigma 15-30. They didn't know, so I took a chance and ordered them up.
How it works, is there is a ring that they provide that has a clip on one side and padding on the other, the nose of the filter goes under this clip and it rests on this padding so that the filter stays perpendicular to the rear element of the lens.
The sigma lens already has this clip kind of design
to slip the gel's under. Gels are extremely tin, just a tad thicker than cellophane.
It turns out that the clip provided is slightly larger than the part that would be removed that it would replace, and also the screw holes don't line up on it and the sigma lens.
The bottom line is, this set of filters is NOT compatible with my Sigma 15-30, which is a shame. Aurora might be able to make a clip part that would work, but I don't know if they would justify the engineering effort involved for a 15 year old lens. This Sigma 15-30 was widely sold as at that time it was the best option for the new digital camera owners to get a wide angle lens to use with their APS-C sized sensors in the new cameras like the Canon D30, D60, 10D. This was before the invention of the EF-S lenses specifically engineered for the crop bodies.
I don't know how many of these lenses are still in active use. I've certainly gotten my use out of mine, as it's still my primary non-fisheye ultra-wide angle lens.
One day those old school cameras with real film will be needed again.
No doubt. I have quite a bit of black and white film and camera both 35mm and 120 and the chemicals to develop. Some of the most iconic images in American history are of the Great Depression.