One Tech Tip: How do you use an f-stop?

Film photography is experiencing a renaissance, especially among young people who love its unique look and analog vibe.

But while Generation Z and younger Millennials are embracing film, analog cameras aren’t as easy to use as the digital cameras they grew up with. What does ISO mean? What is an f/stop anyway? How to determine the correct opening?

George Walker IV, an Associated Press photojournalist based in Nashville, helped describe the basics of film photography for this week’s One Tech Tip.

Walker, who joined the AP in 2023 after 30 years as a photographer at The Tennessean newspaper, said shooting on film is a good way to learn the basics of photography because it “forces me to be patient and focus on taking the photos that matter.”

“You have a finite number of frames on a roll of 35mm film, usually 24 or 36. And you have to make those frames count.”

Before the advent of digital cameras in the early 2000s, photography relied on physical film rather than electronic files stored on memory chips.

Photographic film is a light-sensitive cellulosic material used to create images, by exposing the silver halide coating through the camera lens to create a latent image on the film which is then used to make photographic prints.

This results in images with a distinctive grainy or unfiltered feel that appeals to analog fans put off by digital photos that look too perfect. Enthusiasts are also drawn to cinema as an antidote to digital fatigue and the instant gratification of their smartphones. It’s part of a broader revival of old-school hobbies and content that includes vinyl records, knitting and letter writing.

There are several formats, but the type used in most consumer cameras is 35mm, which comes in small cartridges. Buy it at a photo store or online. Some pharmacies also sell films but the choice is often limited.

When purchasing film, pay attention to the ISO standard, also called film sensitivity. The higher the number, the more sensitive the film is to light.

To shoot in low-light conditions, such as a basketball court or a night football game, photographers can use film rated at ISO 1600 or higher. To capture a scene in bright sunlight, an ISO value of 400 or lower is best.

Beginners should consider black and white film, which is more forgiving than color for exposures and requires you to focus on the composition and lighting of a shot.

These days, new film cameras are limited to a handful of compact, niche or high-end models.

However, there are many used vintage models for sale on eBay and in camera stores. Or try asking around if anyone you know has an old camera forgotten in a drawer.

Look for a model from one of the big five camera makers that dominated the pre-digital photo era: Canon, Nikon, Pentax, Olympus and Minolta.

Cameras that are compact, inexpensive and easy to carry and use. They usually have no controls except a button to turn on the flash.

Single-lens reflex, or SLR, cameras allow you to use fully manual mode. They have plenty of dials and settings, as well as the ability to change lenses, so you can take great photos. If you want to learn and experiment, a fully manual camera is best. But they are also larger and bulkier and can be intimidating for novices.

If you can’t decide, a good rule of thumb is that the best camera is always the one you have with you.

Now that you have film and a camera, it’s time to put them together.

With a manual camera, open the back and insert the film leader, or tip, into a slot on the spool on the right. Use the take-up lever to advance the film to ensure it is properly engaged. Close the camera. When you wind the film, the rewind button on the left rotates if the film is loaded correctly.

The process is a little easier with compact cameras, which usually have automatic winding. There should be a label inside indicating where to position the film leader. If this is not done correctly, you will either receive an error message or the film counter will not advance.

Now that the film is loaded, be sure to keep the camera closed until you have finished taking exposures and the film is completely rewound into the cartridge, otherwise you will ruin the entire roll.

If you’ve decided to get a manual camera but don’t know how to use it, you’ll need to learn how to control exposure by adjusting the shutter speed and aperture, also called f/stop, and setting the film speed or ISO.

When it comes to exposure, think of a tap filling a glass. The f/stops control the flow of water – or the light hitting the film. So f/16 looks like a net while f/2.8 is a fire hose. Shutter speed, on the other hand, controls how long the tap stays open.

F/stops also control the depth of field or amount of focus in the photo. The smaller the f/stop, the greater the focus.

Shutter speed is used to capture action, such as a racing car or a bird in flight. Exposures made with a fast shutter speed of, say, 1/250 or 1/500 of a second or faster are better for freezing action.

Manual cameras usually have a light meter visible through the viewfinder that indicates whether you have the correct exposure.

With a manual camera, you’ll also need to focus the image by hand, which takes practice. When photographing people or animals, make sure the eyes are in focus. For still lifes and landscapes, focus on what you think is important to see, such as a flower petal or a mountain peak.

The technology is different, but the principles are the same. The number one rule is to fill the frame with what you want to see. And study the professionals and masters of photography, such as Gordon Parks, Henri Cartier-Bresson and Ansel Adams.

You can have the film processed at a pharmacy or photography store, or mail it to an online lab. Some cities have community darkrooms that photographers can join.

Processing a film takes time and money, which vary depending on the desired deadline; whether in color or black and white; the number of exposures; and other services.

You can also collect the negatives, those strips of film exposed and developed. It used to be important to keep them in case you wanted to print extra copies later. Today, with photo labs offering digital files as well as physical prints, many people don’t bother to collect them, although most experienced photographers prefer to keep them.

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