How to Load, Advance and Rewind Film: 35mm and 120

Loading film is the first small ritual of film photography, and the one that makes most beginners nervous. It need not. Whether your camera takes 35mm canisters or 120 rolls, the job comes down to a few calm steps: open the back in subdued light, seat the film, catch the leader, check that it is advancing, close up and wind on. Rewinding at the end is just as simple once you know what to feel for.

This guide walks through loading, advancing and rewinding 35mm film, loading and unloading 120 roll film, the small checks that prevent blank rolls, and what to do when something jams. Take it slowly the first few times. After a handful of rolls, it becomes second nature.

Before you start

A few minutes of preparation save a great deal of frustration.

• Find some shade. Film is protected by its canister or backing paper, but bright sun can still sneak in at the edges. Load in the shade of a building or your own body, or indoors away from a window.
• Check the camera is empty. Look at the frame counter or the small window on the back. Some cameras have a little indicator that shows a film is inside. Opening a loaded camera fogs the film.
• Check the battery. Many film cameras need a battery for the meter, the shutter or the motor. A flat battery can make a camera seem broken.
• Know your film speed. Look at the ISO printed on the box. You will set this on the camera, or check that the camera reads it automatically.
• Clean hands, steady surface. Grease and grit on the film show up in every picture. A table or a knee is easier than juggling in the air.

If you are still choosing a camera, choosing your first film camera explains the different types and what to check on a used one.

Know the parts you will touch

Every 35mm camera has the same few parts inside the back, even if they look a little different from model to model.

• The film chamber. On one side, usually the left, is a space shaped to hold the canister. A small fork or spindle at the top engages with the canister’s spool.
• The rewind knob or crank. Above the film chamber on the top plate. On many manual cameras, pulling it up opens the back.
• The sprockets. A toothed roller that engages the holes along the edge of the film and moves it a precise distance with each frame.
• The take-up spool. On the opposite side, a spool with a slot or teeth that grabs the leader and winds the exposed film.
• The pressure plate. A smooth, flat plate on the inside of the back door. It keeps the film flat so the picture is sharp. Never press on it or scratch it.
• The shutter curtains. The delicate panels in the middle of the camera. Keep fingers well away.

For a tour of the rest of the camera, parts of a camera explains what every control does.

Loading 35mm film, step by step

This is the classic method for manual and semi-automatic cameras with a lever to advance the film. Automatic cameras are covered below.

1. Open the back. On many cameras, lift the rewind knob firmly upward until the back pops open. Others have a latch or a sliding catch on the side.
2. Drop in the canister. Place the canister in the film chamber with the protruding end of the spool pointing down. Push the rewind knob back down, turning it slightly if needed, so the fork engages the spool.
3. Pull out the leader. Draw the narrow tongue of film across the camera to the take-up spool. Pull out only as much as you need, roughly one hand width.
4. Catch the leader. Push the end of the leader into the slot on the take-up spool, or hook a sprocket hole onto one of the spool’s teeth.
5. Engage the sprockets. Make sure the holes along both edges of the film sit on the teeth of the sprocket roller, and that the film lies flat across the gate between the rails.
6. Take up the slack. Fire the shutter and advance the lever once with the back still open. Watch the film wrap around the take-up spool and stay engaged on both sides. If it slips, rethread it.
7. Tighten gently. Turn the rewind crank in its arrow direction until you feel slight resistance. That takes up any slack inside the canister.
8. Close the back. Press it shut until it clicks. Check that it is fully latched.
9. Advance to frame one. Fire and advance two or three more times until the counter reads one. These first frames were exposed to light while loading, so they are not used.

The most important check

As you advance to frame one, watch the rewind knob. If the film is moving properly, the rewind knob turns backward each time you advance. If it does not turn, the film is not being pulled through the camera, and every picture you take will land on the same blank piece of film or none at all. This single check prevents the most heartbreaking of all film mistakes: the roll that comes back completely empty.

Already had a roll come back blank or with overlapping frames? Film photo problems helps you trace the cause from the negatives.

Setting the film speed

Your camera’s light meter needs to know how sensitive the film is. On manual cameras there is a dial, often around the rewind knob or the shutter speed dial, marked with ISO or ASA numbers. Set it to the number on the box, unless you are deliberately rating the film differently.

Many automatic cameras read the speed from a checkered pattern of metal and black squares printed on the canister, called a DX code. Small pins inside the film chamber touch the pattern and set the speed automatically. If you load a film without a DX code, these cameras may fall back to a default speed, so check the manual.

Forgetting to change the speed dial after switching to a different film is a classic mistake. A camera set for slow film but loaded with fast film will overexpose, which color negative film usually tolerates; the reverse underexposes, which it does not. If ISO is new to you, it explains what the numbers mean.

Automatic and motorized cameras

Many point-and-shoot cameras and later SLRs load the film for you. You simply drop in the canister, pull the leader across to a mark, usually a colored line or a small symbol near the take-up spool, and close the back. The motor whirs, pulls the film onto the spool and advances to the first frame.

• Line the leader up with the mark. Too short and the camera cannot grab it; too long and it may bunch up.
• Keep the film flat. Lay it across the gate without twisting before you close the back.
• Watch the counter. If the camera displays a blinking zero or an error symbol after closing, the film did not catch. Open the back, reposition and try again.
• Some cameras prewind. A few automatic cameras wind the whole roll out onto the take-up spool when you load it, then pull each frame back into the canister as you shoot. If the back is opened by accident, the frames already taken are protected.

Advancing and shooting

Once loaded, each picture follows the same rhythm: compose, shoot, advance. On manual cameras the lever both moves the film and cocks the shutter, so the camera will not fire again until you advance. On automatic cameras the motor does it for you.

• Advance straight after each shot. It keeps the camera ready for the next moment and stops you forgetting.
• Use a full, smooth stroke. Short, jerky strokes can leave the film partly advanced on some cameras.
• Never force the lever. If it suddenly stops partway, you have probably reached the end of the roll. Forcing it can tear the film from the canister.
• Watch the counter. On a half-frame camera it climbs to about twice the number on the box. Rolls often allow a frame or two beyond the number on the box, but do not count on it.

Holding the camera well matters as much on film as on digital. How to hold your camera explains a steady grip, and camera shake explains why slow shutter speeds blur.

Rewinding 35mm film

At the end of the roll, the film must be wound back into its light-tight canister before the camera is opened.

1. Press the rewind release. On manual cameras, a small button on the base, often flush with the body, releases the sprockets so the film can move backward. Press it once; on many cameras it stays released.
2. Unfold the rewind crank. Flip out the little handle on the rewind knob.
3. Turn in the direction of the arrow. Wind steadily. You will feel gentle tension as the film comes back.
4. Feel for the release. Near the end, the tension increases slightly, then suddenly eases as the leader pulls free of the take-up spool. Give one or two more turns to bring the end inside the canister.
5. Open the back and remove the canister. Put it straight back into its container and label it.

Automatic cameras rewind themselves when the roll ends, or when you press a rewind button. Wait for the motor to stop completely and the counter to show an empty symbol before opening the back.

Rewound your first roll and wondering what to ask the lab for? Getting film developed and scanned explains the order form and what comes back.

Leader in or leader out?

If you rewind fully, the leader disappears inside the canister. This is the safest way to show that a roll has been shot, because nobody can mistake it for fresh film. If you stop rewinding the moment you feel the leader release, a little tongue of film stays outside. Labs are happy either way. Leaving the leader out is useful if you develop at home or if you might deliberately reload the roll for double exposures. Many photographers fold or tear the tip of an exposed leader as a clear signal that the roll is used.

Loading and unloading 120 film

Medium format cameras use 120 roll film, which has no canister. Instead, the film is rolled together with a long strip of opaque backing paper on an open spool. The backing paper protects the film from light, and the frame numbers printed on it are often what you see through a small red window on simpler cameras.

1. Move the empty spool across. The empty spool from your last roll goes on the take-up side.
2. Insert the new roll. Place the fresh roll on the supply side, with the backing paper’s colored side facing out, away from the lens.
3. Break the seal and thread the paper. Peel the paper tab, pull the backing paper across and push its tapered end into the slot on the take-up spool.
4. Wind until the start mark lines up. Turn the knob or crank until the arrows or start marks printed on the paper line up with the marks in the camera.
5. Close and wind to frame one. On cameras with an automatic counter, wind until it stops. On red window cameras, wind until the number one appears in the window.

At the end of a 120 roll, simply keep winding until the backing paper’s tail comes off the supply spool and the whole roll is on the take-up spool. Open the back, hold the roll firmly so it does not loosen, and seal it with the sticky tab. A loosely wound 120 roll can let light in at the edges, causing streaks. The guide to medium format explains the frame sizes and how many pictures fit on a roll.

When film jams or will not rewind

Sooner or later, something goes wrong. Stay calm, because most problems are recoverable if you do not open the camera.

• The lever will not move mid-roll. You may have reached the end early. Try rewinding gently.
• The rewind crank will not turn. The rewind release may not be pressed properly. Press it again and hold it while you start winding.
• Film tears off inside. If the film has pulled free of the canister, do not open the back in the light. Open it inside a changing bag, a light-tight fabric bag with sleeves for your arms, and wind the film by hand into a light-tight container. Or ask a lab to remove it in their darkroom.
• The back opens by accident. Close it immediately. You will lose a few frames to fog, but much of the roll wound tightly on the spool may survive.

Home developers use changing bags all the time. How to develop film at home explains how to handle film in total darkness.

Common mistakes

• Not checking the rewind knob turns. The cause of most blank rolls.
• Loading in bright sun. Light can creep into the canister mouth or the edges of a 120 roll.
• Opening the back before rewinding. Always rewind fully first. If in doubt, rewind.
• Forgetting the speed dial. Set it every time you change film.
• Touching the shutter curtains or pressure plate. Both are delicate and easy to damage.
• Forcing the advance at the end of the roll. It can rip the film from the canister.
• Leaving 120 rolls loose after unloading. Seal them tightly at once.
• Not labeling finished rolls. A shot roll looks identical to a fresh one without a mark.

Try this: a 10-minute loading drill

Practice with an old or expired roll that does not matter, or with a dummy roll from an old developed strip.

1. Minutes 1 to 2: Open the camera back and identify each part: chamber, sprockets, take-up spool, pressure plate.
2. Minutes 3 to 5: Load the film step by step, firing and advancing once with the back open to see the film catch.
3. Minutes 6 to 7: Close the back and advance to frame one, watching the rewind knob turn each time.
4. Minutes 8 to 9: Press the rewind release and rewind, feeling for the moment the leader lets go.
5. Minute 10: Load once more, this time without looking at these steps.

Do this two or three times and you will load with confidence on a windy beach or in a dim room.

Frequently asked questions

Do I need a dark room to load film?

No. 35mm canisters and 120 backing paper protect the film. Just avoid direct, bright sunlight and load in the shade.

Why do I lose the first few frames?

The leader is exposed to light while loading, so the first frames are fogged. Advancing two or three times moves fresh film into place.

How do I know the film is advancing?

On manual cameras, the rewind knob turns as you advance. On automatic cameras, the counter increases and the camera does not show an error.

What happens if I open the camera by mistake?

Close it at once. The film exposed to light will be fogged, usually the frames nearest the back door, but tightly wound film often survives.

Can I change film halfway through a roll?

Yes, with care. Note the frame number, rewind slowly until you feel the leader release and stop, leaving the leader out. Later, reload and advance with the lens cap on past the frames already used, plus one extra.

Does film need to be loaded a particular way up?

Yes. In 35mm cameras the canister only fits one way. With 120 film, the colored side of the backing paper faces away from the lens.

For terms such as leader, sprocket and DX code, see the photography glossary, and for the bigger picture of shooting film, film photography covers formats, stocks and metering.