I've heard a lot of stories about different materials being used for lens diffusion (including petroleum jelly, better known as Vaseline, being smeared on the lens), but never one this ingenious and cheap -- and it actually seems to work very well. Shane Hurlbut is incredibly forthcoming with his experiences and advice, and this time he's talking about a particular way of diffusing a lens that uses women's stockings over the rear element. This softens the image just a bit, but mainly it gives a dreamy glow to the highlights and blown out areas of the image. He's done a video showing the before and after with some Arri Master Primes and a Canon C300, but this effect will work on literally any removable lens camera system, from DSLRs to RED Epics.
Shane Hurlbut Fogal Net Test:
Below is a photo showing the comparison between the stocking on, and off, the lens:
Here is the look in action on one of Shane's first films, The Rat Pack:
There's no question it's an interesting effect, and the fact that it's a cheap solution makes it even more enticing to try. The soft glow that comes from using the stocking is technically imperfect, but that's the idea, technical perfection does not always allow for the best image -- just like using some older lenses can give you an interesting look. If you're using still photo lenses instead of expensive PL lenses, it seems like the effect will work much better if the stocking is right on the element, so if the rear element is recessed for any reason, it might be tough to safely get the stocking onto your lens.
Back in the day, a Director of Photography rarely used a camera without some sort of filter over the lens, whether for creative effect or proper exposure. These days, with the ability to do a tremendous amount of post-processing, that technique is falling out of favor with digital cameras. If you've got a specific look that you want to achieve, even with digital technology, it's still helpful to get as much of that look on-set as possible.