Seems a lot of confusion about fast flash sync FP. Some call it "Fast Pulse", some call it "Focal Plane", but what it really is? Everything happens at focal plane, so naturaly FP is called "Focal Plane" and fits many people well. Fast Pulse perhaps makes more sense, and fits many more people. How about Forward Point? - that depends how deeply you are willing to understand it. When we talk about high speed flash synchronization, perhaps FP means something else? I think FP is an electronic implementation of the Forward Point flash synchronization. Where FP came from? In older days, it was possible to have very fast flash synchronization, faster than the camera x-sync speed, with a slow burning single use bulbs. This was done with single burn bulbs that contained a magnesium powder and blasted one shot of light. Since the burning required some time from ignition to full brightness, a Forward Point (forward in time) was used for this type of synchronization. The FP voltage signal was sent to start burn the bulb at the time when SLR mirror started moving up. For electronic flash there is an X-Sync method. X-sync trigger signal is usually sent to electronic flash when a focal plane shutter is open wide - presumably as wide as the width of the film frame (on horizintal travelling focal plane shuttere) - this is for single shot lighting. Faster than camera x sync shutter setting results in shutter openning narrower slot, much narrower than the frame width (or frame hight on vertical travel shutters). The shutter narrow slot sweeps across the film plane, but at any time only a narrow part of frame is exposed to the light. Magnesium burning bulbs provided bright flash lasting longer than the time needed for the shutter slot to move across the film frame. This way entire frame was exposed, and the shutter was faster than X sync. The Forward Point (forward in time) was needed to accomplish this without electronic flash involved. When single shot electronic flash is used and shutter is set faster than X sync, only a narrow portion of the film is exposed. (this is usually prevented on modern electrionic cameras). It is technically difficult (or impossible) to prolong duration of an electronic flash to cover entire time event of narrow shutter slot traveling across wider film frame. Once the high voltage capacitor is shorted through the flash bulb by the trigger signal of the shutter, it just blasts too fast to cover entire film frame. To implement electronic equivalent of the old FP method, it was necessary to design flash units that produce multiple flash blasts (strobes) is sequence and adjucent to each other, thus effectively prolonging the duration of the flash to cover time required for narrow shutter slot travel time. What happens in some Nikon and Canon flashes that have FP (also called a high speed sync or something like it). When camera is set to speed faster than the X Sync, and the flash is set to FP, then the flash computes how many strobes it needs to cover entive frame with consecutive blasts. Max power of each strobe in sequence is limitted to allow power for the rest of the remaining number of strobes to make, so the maximum range of the flash unit is reduced by the number of flashes needed. I think FP stands for electronic implementation of Forward Point technique, a technique that allow faster than X Sync shutter speeds with flash. This is now basically a technique that allows to substitute one blast with multiple electronic strobes that are adjucent and (hopefully) equal in strength. I think if you explain FP as a focal plane, you will not prompt for additional questions. If you explain FP as Fast Pulse, perhaps no one will ask more. However, if you try explain FP as Forward Point, certainly this could trigger an avalanche of questions. As long as it works and people are happy, let FP be called anyway you wish.