Hello,

I've found a weird banding issue across a lot of my Mavic Air footage. I can't figure out what it is... I don't think it's the propellors (although I might be wrong) as it's not necessarily at the top of the image. A short pronounced version can be seen here: but have many other examples that aren't as pronounced over long peroids.

Thanks in advance for any help

Cheers,
Jon

They might be the shadows of the propellers. Did you use a fast shutter speed?

Yes I did...

Although in this clip I'm pointing away from the sun:

It looks like typical of shots when the clear gimbal cover is on.   Is it?

Griffith Posted at 2018-3-13 04:54
It looks like typical of shots when the clear gimbal cover is on.   Is it?

Haha, afraid not. I can be silly sometimes but not that silly!!

ukjoncollins Posted at 2018-3-13 04:47
Although in this clip I'm pointing away from the sun: https://vimeo.com/259856692/fa36260a5b

Hi I saw this vid on YouTube and one guy had the same issue and it was his the filter that he was using on his Mavic Air. His theory was the may have been some strange reflection due to the gap between the filter and the lens or poor quality filters.

Hope your find the solution!

Mini-G Posted at 2018-3-13 05:03
Hi I saw this vid on YouTube and one guy had the same issue and it was his the filter that he was using on his Mavic Air. His theory was the may have been some strange reflection due to the gap between the filter and the lens or poor quality filters.

Hope your find the solution!

Definitely looks like prop shadows to me. Were you flying aggressively at the time they appear?

QuadKid Posted at 2018-3-13 05:20
Definitely looks like prop shadows to me. Were you flying aggressively at the time they appear?

Not really... with a very fast shutter though. I figured if I just left it on auto exposure with no ND on the front, I can add in motion blur later. I hadn't realised prop shadow was a thing...

In both cases, the bright spot is just off camera, so I think it is prop shadows.  The first one shows a reflection from the water and it looks like the sun direct on the second one.  There is also a slight lens flare on both just before you pan into the bright spot.

AG0N-Gary Posted at 2018-3-13 05:36
In both cases, the bright spot is just off camera, so I think it is prop shadows.  The first one shows a reflection from the water and it looks like the sun direct on the second one.  There is also a slight lens flare on both just before you pan into the bright spot.

Thanks mate. That's cleared that up then. In your experience, would ND on the front help prevent that?

ukjoncollins Posted at 2018-3-13 05:38
Thanks mate. That's cleared that up then. In your experience, would ND on the front help prevent that?

I doubt it.  You need a lens shade if you are going to shoot the angle to the sun.  You've already stated you don't have the clear cover on, so you just need to keep the sun from coming into the side of the camera lens.  Also make sure the lens is VERY clean.  Any haze on the lens will make the prop shadows show more.

AG0N-Gary Posted at 2018-3-13 06:18
I doubt it.  You need a lens shade if you are going to shoot the angle to the sun.  You've already stated you don't have the clear cover on, so you just need to keep the sun from coming into the side of the camera lens.  Also make sure the lens is VERY clean.  Any haze on the lens will make the prop shadows show more.

OK, that's great to know. Lens hood and a clean lens it is.

You can tell by the movement that it is prop shadow, I wonder if a polarizing filter would eliminate it? Anyone know.

Grmachine Posted at 2018-3-13 06:47
You can tell by the movement that it is prop shadow, I wonder if a polarizing filter would eliminate it? Anyone know.

Interesting idea... I figured ND with a shutter of 1/50 would at least smudge it out. But if you could angle the polarizor correctly, in theory that would work.

ukjoncollins Posted at 2018-3-13 04:55
Haha, afraid not. I can be silly sometimes but not that silly!!

Especially in the second video - looks like a sun reflection off a shiny part - may be just the lens.  It appeared to occur when the camera panned across a certain compass direction - first panning in one direction, then back across.  You may want to consider using one of the blackened partial gimbal covers.

It looks to me like shadow from the props. It matches the location of the sun and disappears in certain directions.
Get a sunhood if you want to get rid of most of that.
Or move the gimbal down a bit.

Please do not fly your drone toward sun and you can try to adjust the camera to proper position. Thanks for your support.

Watching on a 4k tv that is definitely prop related.

ukjoncollins Posted at 2018-3-13 05:38
Thanks mate. That's cleared that up then. In your experience, would ND on the front help prevent that?

Someone else on the forum told me they thought ND filters would remove or at least lessen prop shadows. I am using ND filters now and have not had any prop shadow issues since I started using them. I have only had a few days of flying with the ND filters though. One of the days though I shot a variety of angles that I would expect to possibly cause this issue.  The filter I used on that day wasn't ideal. I really should have had a darker filter for the light level, but I think that it may have been enough to blur the prop shadows. I think ND filters are worth trying. I didn't realize at the time I purchased mine that they could help with prop shadows and props getting in the shot, but I think that they do help.

The ND filters probably do not completely remove the prop shadows, but they will blur the shadows so that you don't get the flickering effect. The shadow intensity will likely be so low that you will not notice the shadow on the video. I haven't seen any lens shades available for the Mavic Air but if you can find one, that would help too.

I live in California. I am guessing that on a bright day, the most likely correct filter choice is going to be ND32. This did not come in the set that I ordered from Polar Pro so I have ordered the "Limited Collection" set. They have an app for calculating the correct filter to use. You might want to download the app and do some tests before ordering.

Tom_A Posted at 2018-3-18 10:02
Someone else on the forum told me they thought ND filters would remove or at least lessen prop shadows. I am using ND filters now and have not had any prop shadow issues since I started using them. I have only had a few days of flying with the ND filters though. One of the days though I shot a variety of angles that I would expect to possibly cause this issue.  The filter I used on that day wasn't ideal. I really should have had a darker filter for the light level, but I think that it may have been enough to blur the prop shadows. I think ND filters are worth trying. I didn't realize at the time I purchased mine that they could help with prop shadows and props getting in the shot, but I think that they do help.

The ND filters probably do not completely remove the prop shadows, but they will blur the shadows so that you don't get the flickering effect. The shadow intensity will likely be so low that you will not notice the shadow on the video. I haven't seen any lens shades available for the Mavic Air but if you can find one, that would help too.

Cool, well I tend to stick motion blur on my shots anyway in post to bring the shutter speed back down and that seems to be smoothing out the less obvious bits.

In terms of lens hood, I've found these: https://www.ebay.co.uk/itm/Mini- ... 2057872.m2749.l2649 but it's not arrived yet...