As is common when using a HSS strobe, the first jump in shutter speed settings from normal sync to HSS (High Speed Sync) on the FJ400 will reduce the light recorded on the image. The amount of that reduction will be dependent on how your camera handles HSS. Some systems will see less recorded light loss while others will record a more significant decrease. Additional increases in shutter speed while in HSS will reduce the recorded output similarly to the light lost when adjusting the shutter speed in an ambient light setting. For instance, raising the shutter speed from 1/250 normal sync to 1/500 HSS may see a total drop in recorded output by 2 stops or 1/4 the amount of the normal sync. Moving from 1/500 (HSS) to 1/1000 (HSS) and each additional doubling of the shutter speed would see only an additional 1 stop drop or 1/2 the amount of the previous setting. Since HSS is typically employed to allow wider apertures using higher shutter speeds, the reduced recorded output may not have a significant impact on how end users use the HSS feature.
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