Take pictures of clothes hanging with Nikon D3 100, equipped with four cameras, and the picture is always dark.

Four-headed photographic lights? Is it the kind that uses fluorescent lights? If so, there is something wrong with your camera settings. For the normally lit lamp, just use P or A gear. Your original settings are some common settings of a studio flash, such as setting the shutter at 125 seconds, and then only adjusting the aperture to ensure accurate exposure. If you use this constant light, it is estimated that the shutter speed can reach one thirtieth of a second.