Flying Over Water, Camera Question

[BeeRAD56]

I took the trusty H out for my first flights over water today.

Lot's of fun video with the exception of some sort of noise or what I would call fluttering at the bottom of the screen when pointed toward the sun. The flights were between 2 & 3 in the afternoon so the sun wasn't low in the sky but not directly overhead either. When turned away from the sun the fluttering stops.

I was shooting in auto for both WB and exposure at the default resolution and frame rate. My altitude above the water varied between 15 and 50 feet. The flutter also seemed in sync with the prop frequency.

Does anyone have insight to this issue.

Thanks!

 

[Eagle's Eye Video]

Shadows from the props... use ND filters to slow the effective shutter speed and reduce that artifact.

 

[Steve Carr]

I took the trusty H out for my first flights over water today.

Lot's of fun video with the exception of some sort of noise or what I would call fluttering at the bottom of the screen when pointed toward the sun. The flights were between 2 & 3 in the afternoon so the sun wasn't low in the sky but not directly overhead either. When turned away from the sun the fluttering stops.

I was shooting in auto for both WB and exposure at the default resolution and frame rate. My altitude above the water varied between 15 and 50 feet. The flutter also seemed in sync with the prop frequency.

Does anyone have insight to this issue.

Thanks!

You are seeing the effects of sunlight passing through the props. I've seen it many times.

 

[PatR]

It's called prop flicker. Happens when the sun causes the propellers to cast a shadow that falls across the lens. It's more prevalent when running a bare lens. ND filters cut the shadows. The rub is there's no shadows because the filter cuts the amount of light entering the lens. Lenses need as much light as they can get. Ultimately, as you gain experience you develop instinct that causes you to avoid the conditions that cause prop flicker. Also, put the gimbal switch at the top left of the-16 in the upper position. That will limit the upward angle allowed to the gimbal, further reducing the chance of flicker.

If you're still using the clear filter that came on the camera, consider removing it. That little piece of plastic cuts down on light too. Your images will be better without it. Just clean the camera lens once in a while

 

[BeeRAD56]

Shadows from the props... use ND filters to slow the effective shutter speed and reduce that artifact.

Thank you. Do you have a recommendation for a beginner on a set of filters?

 

[Eagle's Eye Video]

Actually the artifact is reduced because the ND filter reduces the amount of light reaching the sensor, and the auto-exposure
slows down the shutter speed (or manual setting the shutter speed to a lower speed). For instance, without the ND filter in
full sunlight, your effective shutter speed will be about 1/2000 of a second at ISO 100. This is fast enough to see the shadow
of the props.

When the ND filters are used the effective shutter speed will drop as the strength of the ND filter increases. So with a ND8
filter the shutter speed will drop to about 1/250 of a second, which is slow enough for the prop's shadow to blur enough to
no longer be a noticeable artifact.

BeeRAD, here is a suggested set:

Polar Pro ND filters

 

[BeeRAD56]

It's called prop flicker. Happens when the sun causes the propellers to cast a shadow that falls across the lens. It's more prevalent when running a bare lens. ND filters cut the shadows. The rub is there's no shadows because the filter cuts the amount of light entering the lens. Lenses need as much light as they can get. Ultimately, as you gain experience you develop instinct that causes you to avoid the conditions that cause prop flicker. Also, put the gimbal switch at the top left of the-16 in the upper position. That will limit the upward angle allowed to the gimbal, further reducing the chance of flicker.

If you're still using the clear filter that came on the camera, consider removing it. That little piece of plastic cuts down on light too. Your images will be better without it. Just clean the camera lens once in a while

Thank you. I've haven't noticed this prop flicker until today when flying over water. It must have something to do with the suns reflection off the water?

 

[Eagle's Eye Video]

Thank you. I've haven't noticed this prop flicker until today when flying over water. It must have something to do with the suns reflection off the water?

In your case probably, because that artifact usually occurs in the upper part of the frame...

 

[BeeRAD56]

Actually the artifact is reduced because the ND filter reduces the amount of light reaching the sensor, and the auto-exposure
slows down the shutter speed (or manual setting the shutter speed to a lower speed). For instance, without the ND filter in
full sunlight, your effective shutter speed will be about 1/2000 of a second at ISO 100. This is fast enough to see the shadow
of the props.

When the ND filters are used the effective shutter speed will drop as the strength of the ND filter increases. So with a ND16
filter the shutter speed will drop to about 1/250 of a second, which is slow enough for the prop's shadow to blur enough to
no longer be a noticeable artifact.

BeeRAD, here is a suggested set:

Polar Pro ND filters

Thank you for the recommendation on some filters. I'm going to give them a try.

 

[Atomic08]

Get these while you can !
PolarPro - Circular Polarizer and Neutral Density Lens Filters for Yuneec Typhoon 4K and H (3-Count) - Black
$14.99
CLEARANCE

PolarPro - Circular Polarizer and Neutral Density Lens Filters for Yuneec Typhoon 4K and H (3-Count) - Black

 

[Ty Pilot]

Atomic08, Yep, I was just going to post that link too, these are great filters for the H and a steal at that price. The set I got was just three ND filters as shown, I think your link is to the same set.

 

[BeeRAD56]

Get these while you can !
PolarPro - Circular Polarizer and Neutral Density Lens Filters for Yuneec Typhoon 4K and H (3-Count) - Black
$14.99
CLEARANCE

PolarPro - Circular Polarizer and Neutral Density Lens Filters for Yuneec Typhoon 4K and H (3-Count) - Black

Thank you! That's a great deal and a set is on the way!

 

[Eagle's Eye Video]

Get these while you can !
PolarPro - Circular Polarizer and Neutral Density Lens Filters for Yuneec Typhoon 4K and H (3-Count) - Black
$14.99
CLEARANCE

PolarPro - Circular Polarizer and Neutral Density Lens Filters for Yuneec Typhoon 4K and H (3-Count) - Black

Very cheap... enough so that I may pick up a set as a backup.

 

[Rubik]

Using ND filters is a good plan.
To combat sun flare and prop shadows, I made an "eyebrow" and epoxied it to the ND16 filter (photo). The eyebrow is made from an aluminum soda can (Sprite, I believe). It took a bit of trial and error to get the shape right. I wanted maximum shading without being visible to the camera. It works great for 16:9 video but is still visible in 4:3 stills. I usually crop the stills anyway.
Here's a frame grab from a video shooting directly towards a Spring mid-day sun and a 4:3 still from the same flight.