The right tool for the job
When choosing film, it is important to get the right film for the job. After all, a carpenter wouldn't grab a hammer to saw a 2x4. The wrong film could ruin a picturesque view or perfect memory and, what's worse, it wouldn't be known until the film is developed! The most important factors when choosing film are film speed, type and brand.
ISO speed
The ISO speed on the side of the film box tells you roughly how sensitive to light a film is. Light sensitivity translates into film speed, or, the length of time a frame is exposed to light. Film speed is important when trying to capture movement. The longer a frame is exposed, the more likely the object will look blurred, as the movement will be captured on one frame.
So why wouldn't a photographer want to use high speed film, like ISO 800, all the time? Because slower film has superior color and detail, as well as a finer grain picture.
As long as the subject (and the photographer) remains still for the length of the exposure, this type of film is a far better performer. Slow film is ideal for portraits and landscape; when quality and accuracy is paramount.
Film type
Most film cameras take some form of 35mm film. This comes in the standard rolls and the new Advanced Photo System, an automatic loading roll system popularized by FujiFilm. Camera shops give photographers basic options of color negative, color positive and black &white negative.
Color negative is a good general performer, allowing for making accurate prints cheaply and easily because the film never gets too dense. It can be run through cheap scanners at a budget 1-hour photo shop without much worry.
Negative film is ideal for most situations when light exposure varies and when a scene contains detail in a range of tones. Black & white negative features the same benefits in a monochrome form with the added advantage of greater contrast control and archival quality prints.
Negative film is the most common medium for film cameras.
Color slide film, or color positive film, offers greater detail and is generally cheaper than negative film. This type of camera film is preferred by professionals who sell their photographs for print.
Color slide film, while it gives a quick pre-printing representation of the photograph, requires a knowledgeable printer and may not be able to be developed and printed anywhere.
Brand
Most photography enthusiast websites agree that choosing a "BrandX" roll of film is not a good idea when quality is important. The top brands of consumer film are Kodak, Konica and FujiFilm, companies with a reputation for quality and consistency in their film products.
Other companies, such as Agfa-Gevaert, Foma and Solaris offer better film, but is geared towards the knowledgeable enthusiast. Experimentation is necessary on the part of the photographer to find the brand and type of film that suits them best, however.
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