When you are using TTL flash (metered, automatic), you sometimes get too-dark foregrounds.
This can be because a setting is wrong, or because there is just not enough power available from your flash. It is important to know which one it is!
The settings that affect your flash brightness are:
- Aperture
- ISO
- Shutter, after a point (because exceeding the synch speed and using “fast flash” means you lose power)
- Distance
- Flash Power
- Flash zoom
My trick: to ascertain whether it can be done at all, fire a test shot using manual flash at full power!
- Set your camera to its max sync speed (eg 1/200th sec)
- Set flash to manual (take the flash off TTL and set it to M).
- Adjust it to full power (not TTL but M, and power at 1/1, or 100%).
- If your subject is centered, zoom in the flash head (lighting edges that have no subject only wastes power).
If your picture’s flash subject is now still too dark, it cannot be done. Open the aperture or get closer.
But if your flash subject is now blown out, it means your picture can be done with current distance. Go back to TTL, figure out what you are doing wrong, fix it, and try again!