If you're shooting a university's graduation, then odds are that most of the people in attendance are from out of town and plan to leave soon. In addition to the camera, tripod and flash, you should also have a great photo printer so that you can deliver the goods on the same day.
Polymerase chain reaction. Polymerase chain reaction, (PCR), a technique used to make numerous copies of a specific segment of DNA quickly and accurately.
Because unrelated people will almost definitely differ in their number of repeats, STRs can be used to confidently discriminate between unrelated persons. DNA is isolated from material collected at the crime scene. The STR loci are amplified by PCR using sequence-specific primers. These primers are designed in such a way that they can amplify the STR loci from any individual. The resulting DNA fragments are then processed using electrophoresis.