Most of the time if you say your image came out too dark someone in the room will chime in with "use a flash". "You need a flash" is all to glib an answer for such a complex subject. While adding flash to your images will increase the amount of light available, it is not a "cure-all" for dark photographs. Another way to increase recorded light is to use a faster film speed. This will decrease the amount of light needed to record the image.
Beyond the immediate answers of flash and film speed there are several more reasons as to why images may turn out too dark. In general, there was a reason you may have not realized how much light was needed or why you captured the wrong amount of light.
- Causes of Improper Light Recording
- Incorrect Shutter Speed/Aperture/Film Speed Combination
- Metering Off of Wrong Spot in Composition
- Inaccurate Light Meter
- Old and/or Damaged Film
- Improper Developing