Through A Glass Darkly - With Lee, et al.
We are frequently consulted by clients as to how the can make people disappear from their images. Apart from the convenient suggestion of using Sarin or the services of the Ton Ton Macout, we also have a series of technical exercises that can be done with equipment available here in the shop:
1. If it is just one person in an image, erase the offending individual with the content-aware eraser in Photoshop Elements 11. This brush looks around the image and draws inspiration from whatever the subject is standing next to and then repeats this in a convincing manner to replace them. It is surprisingly effective - I made light fittings and an entire Volvo prime mover disappear from a wedding shot by these means. Fun wedding.
2. If it is a larger area that needs to be depopulated, mount a very heavy neutral density filter in front of the lens and let the shutter stay open for a very long period of time. All the movers and shakers in the picture will be gone. Of course you will also have movement in clouds or water but this can be a great aesthetic result as well.
3. Lure the people away with a promise of something for free - or scare them away with the threat of something for free.
Okay, look at the heading picture. Lots of manufacturers are onto this need - B+W make a 1000X graufilter that is 10 stop. Kenko make a filter that they refer to as ND400 that is effectively 9 stops. Lee make a square filter for their own holder system with the delightful name of The Big Stopper. This is also 10 stop but that is such a great name that it is the one that sticks in people's minds - we just wish that Lee were more efficient in supplying it to our shop as people sometimes have to wait a while for it. Note that you can also get a very deep blocking of light with the Kenko R72 Infrared filter but this is entirely different as an effect from the more predictable one of a pure ND. It can be extremely interesting but funky.
You could stack ND 8 filters together to achieve considerable darkening but you'd be adding glass surfaces to degrade the resolution. Decide yourself if this is a good idea.
Oh, while I remember it - you can also do this by going with a good old paper negative in a good old 4 x 5 camera with a good old red yellow filter in front of an f:128 lens but this would require you to be both good and old. I have managed only part of the equation...