My film came back completely black

Likely causes

1. 1.

   The film was fogged by light before development

   Common

   How to tell

   The whole strip is dense, including between frames and over the edge markings, which may be hard to read. Often happens when a camera back is opened mid-roll or film is loaded onto a reel with a light on.

   Fix

   Load reels in total darkness (a changing bag works) and check your room is truly dark: sit in it for five minutes and look for light around doors.

2. 2.

   Severe overexposure

   Occasional

   How to tell

   Frames are very dense but the gaps between frames and the edge markings look normal.

   Fix

   Check the ISO setting, the meter, and that the shutter isn't sticking open at slow speeds.

3. 3.

   Massive overdevelopment or the wrong developer

   Rare

   How to tell

   Everything is dense, edge markings are very heavy, and the film base itself looks grey.

   Fix

   Check time, temperature and dilution against a trusted source before the next roll.

Avoiding it next time

• Never open the camera back until the film is fully rewound.
• Test your darkroom or changing bag for light leaks.

Go deeper

• Development Problems Troubleshooting →
• Light Leak Diagnosis and Repair →
• Development times →

Other negatives problems

• My film came back completely clear
• My negatives are thin and weak
• My negatives are very dark and dense
• There are streaks or flares of light on my photos
• My negatives have uneven streaks or patches
• There are spots on my negatives
• There are water marks on my negatives
• There are long scratches along my film
• My black and white negatives have a pink or purple tint
• My negatives look milky or cloudy
• My negatives have a cracked, crazed pattern
• There are small crescent-shaped marks on my film
• My colour photos have a strong colour cast
• The edges of my 120 frames are fogged

Last checked October 2026. Seen something different? Tell us.