How to get cinematic drone videos with Polar Pro ND Filters
Frame rate vs. shutter speed
To achieve the dream, you need to follow the 180 degree shutter rule. The camera shutter speed should be no greater that twice the frame rate (fps).
- If at 24fps then shutter speed = 1/50th of a second
- If at 30fps then shutter speed = 1/60th of a second
- If at 60fps then shutter speed = 1/120th of a second
- If at 120fps then shutter speed = 1/240th of a second
Why? Well it’s all to do with the human brain and how much visual information it can process and interpret. Most of us are unaware that we have “un-conscience blindness”. UB is were there is too much information for the brain to make sense, so it works on passed knowledge, filling in with what it expects rather than the reality. Magicians use this process to great effect for performing slight of hand.
Set in Stone.
Rules are made to be broken. If you want to un-nerve your audience, then miss match your frame rate/shutter. The image maybe properly exposed, well framed, but the off frame rate/shutter speed combo with make watching uncomfortable, but the audience will not know why. Horror films use this at key moments. Saving Private Ryan opening scene with the beach landing used this deliberately to add to the drama.
Yes, break and push the rules, but like any good recipe, sprinkle sparingly.
Using ND filters to slow shutter speed.
Polar Pro have made life easy for the DJI UAV/drone flyer looking to get cinematic. The Polar Pro app, available for iOS & android, helps you select the right ND filter for perfect exposure and hit the 180 degree shutter rule.
Once the correct one is selected, the ND filter acts like a pair of sunglasses. Reducing the amount of light allowed to hit the camera sensor, allowing the operator to slow the shutter speed down.
On a test with the DJI Mavic Air shooting video at 24 fps, a Polar Pro Cinema ND16 filter reduced the shutter speed down from 1/800th of a second to 1/50th of second. At this shutter speed, any movement with have the right amount of visual blur the human brain can accept.
Practice makes perfect
There is enough going on when you flying a UAV/drone without adding ND filters into the mix. My advise if you want that cinematic look is to get out of auto as soon as you can. Best way to master the use of ND filters is to say on the ground.
After an hour or so, you will have cracked the mystery of ND filter/exposure/shutter speed. practice, practice, practice. Checkout how to get perfect exposure here.
Once mastered why not upload your video and share your footage? Well shot footage, hitting the 180 degree shutter rule will be more appealing on stock sites. Get clip-mining.