Sigma produces a line of external camera flashes.
The Sigma EF-500 Super Flash is an external camera flash manufactured by Sigma and designed to work with film and digital single lens reflex cameras. Third party companies like Sigma and others produce equipment to work with Original Equipment Manufacturers (OEM) like Canon, Nikon, Pentax, Olympus and others. Often equipment manufactured by third party manufacturers will sell for less than the OEM models and offer the same functionality. If the Sigma flash is not performing correctly, you can perform a few tests to troubleshoot the unit.
Instructions
1. Check the flash unit's focal length setting. The EF-500 Super Flash has been reported to not line up with the same focal length of the lens that is being used. This is not too much of a problem if the flash is wider than the lens, but if the lens is a 28mm and the flash sets at 50mm, it is possible that the flash will not provide equal light coverage of the scene. If you are using a zoom lens, rotate the focal length ring and see if the appropriate setting registers on the flash.
2. Measure the output using a flash meter. Perform a number of tests. Set the flash at its maximum output and discharge the flash by pressing the "Test" button. Write down the exposure the flash meter reads. Discharge the flash as soon as it signals it is ready, and write down the number and compare to the first test.
3. Replace the batteries and clean the hot shoe contacts. With most electronic devices, if the batteries start to lose power the performance is compromised. Replace the batteries with new or freshly charged units before you start to use the flash. Clean the hot shoe contacts using a clean eraser on the end of a pencil. If there is a communication problem between the camera and the flash, having clean contacts may help eliminate the problem.
Tags: focal length, Super Flash, camera flash, EF-500 Super, EF-500 Super Flash, external camera