Everyone knows that I'm a big nerd. I have no shame about it. I could talk about cameras and photography and how to craft a perfect lighting situation all day long. But when it comes to the aesthetic and technical differences between analog film and digital pixels, I really get excited. Which is why push processing film is so fun.
'Push processing' film is a technique where you trick your film into thinking it is faster (or more sensitive) than it really is, and then developing it in such a way that it actually becomes a faster speed film. Thus, 'pushing' the film into a higher ISO rating. Really all this means is that the photographer is taking serious creative and technical control of their materials. And when done properly, it produces some amazing results with a spectacular grain.
For my Fine Art dog photography clients, I always use a 400 speed medium format film with my Hasselblad camera. 400 speed film is flexible, it is forgiving, and it is right in the middle of the ISO ratings (ISO is simply a fancy term for film sensitivity or film speed). The reason I use 400 film is because I am tackling a variety of natural lighting situations with each dog photography client- inside, outside, well lit, poorly lit, etc. I am constantly metering and re-metering for each new lighting situation, and 400 film allows me a lot of wiggle room.
But we all know that San Francisco weather changes quickly, and when I am met with a cloudy/gloomy day (which is actually the most beautiful weather to photograph in), or simply a home that is a bit darker than expected- I simply push my 400 speed film to 1600. This allows me to bring in much more light, and have a deeper control of my imagery. The reason I never use actual 1600 or 3200 ISO films is because they are simply too grainy and flat.
I always need to have control over my materials and tools- from the selection of film and chemistry, to how I rate my films, process them, print my photographs, frame them, etc. Pushing my 400 film to 1600 gives me this perfect range of tones, and a wonderful, subtle grain. Film grain is the actual silver particles picking up light, and showing their unique microscopic shapes. It's fascinating, and when done well can add a magical textural element to an image.
Digital pixels are NOT film grain. Digital pixels do not have the same characteristics as particles of silver, nor can they hold as vast a range of black and white tones as film grain. When a digital photograph is overly or improperly manipulated, it becomes pixelated (or 'noisy'), and tones morph into pixelated blobs. Whereas when an analog negative at a high ISO rating get overly manipulated, it keeps the integrity of it's grain and tonal range. Which is why all these analog, manual steps are worth it. Invest in grain, not pixels!