Black soft filters can be used to reduce blemishes and wrinkles in people or objects by reducing the resolution of the image. They can also be used to increase contrast and create a halo or glow effect for specular light sources in a scene. 1. soften the light effect of the actress's facial details, 2. It can effectively reduce some wrinkles and spots on the face of the actor, but at the same time maintain the details and clarity of the character's hair and eyes. 3. It also plays an important role in film shooting. Excellent black mist filter does not affect the color temperature, the use of dim scenes with a hazy age will create the atmosphere of the scene well. 

ND2-ND32 filter allows you to reduce 5 steps, ND8-ND2000 is 9 steps, ND8-ND128 is 5 steps. 

The camea can take 1.6v rechargeable batteries, but in general rechargeable battery might drop its voltage quick depend on its physical performance. In the cold weather, recommend using Energize lithium batteries to get longer lifetime. 

we recommend that you should reduce the density of the filter until "X" cross or trailing smear disappears. 

With this filter, I can reduce my shutter speed, even with a sunny day, so in my photos I get a blur motion background. Same thing with video, you can reduce the shutter speed so you will get more motion blur. It you consider for portrait, this filter don’t add blur background. For that you need a 2.8 or faster lens. I hope this help