What causes "The Blob"?

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Whilst in South Africa, we usually fly in the hour just after sunrise or just before sunset, when the sun is low in the sky. With the sun directly behind us, we've commonly and annoyingly got "The Blob" in frame. This is a small area of light. It shows up on video and on our P4P+ screen whilst flying. To get this "blob" out of frame, we had to manoeuvre the drone to another angle.

Not sure if this was something wrong with the camera (it certainly wasn't any kind of mark on the front of the lens, as it showed up regardless of cleaning or different ND/PL filters), a close colleague contacted various DJI staff in the Netherlands plus several independent drone experts in the UK - sending three short samples of footage featuring "The Blob". We've been sceptical of most of the "explanations" suggested.

The most likely cause (only suggested by two individuals out of 10+) is the reflection of sunlight off a part of the drone being projected ahead onto the landscape (or cloud).

I've once, or perhaps twice, seen this "blob" on other people's footage on this forum.

Here are links to the short clips of footage that my colleague posted to YouTube:

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Some of you are serious experts, highly experienced and far more technically knowledgeable than myself, so I'm hoping this "blob" problem will be known and can be reliably identified.

Thank you, in anticipation.
 
Its looks like lense flare. If so, it's caused by the sun. If you search for "lense flare" images on the internet you will see tons of examples and suggestions on how to avoid it..

If the camera gets pointed in the direction of the sun (at all) it can happen. The sun does not even have to be in the shoot to have the lense flare happen.
 
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Yea. Like a JJ Abrams film.
 
Its looks like lense flare. If so, it's caused by the sun. If you search for "lense flare" images on the internet you will see tons of examples and suggestions on how to avoid it..

If the camera gets pointed in the direction of the sun (at all) it can happen. The sun does not even have to be in the shoot to have the lense flare happen.
As I wrote above, it only happens when the sun is directly behind the drone or direction the camera is pointed. I'm very experienced as a ground-based photographer and know about lens flare, but this isn't like anything I've encountered before.
 
Check both the UV filter and the actual camera lens for dust by unscrewing the UV Filter? Sometimes light can bounce in between the filter and lens and any dust sticks out like a sore thumb. Have you tried an ND filter to see if it is still there?
 
My P4 shows them too. It aligns with the suns rays bouncing back at the craft on the vegetation or ground or mist... I rarly see stuff close to this on my DSLR but then I'm not 300 feet looking down to earth with the sun in my back. I guess when your close to 180 degree reflection we get the oportunity to get annoyed by it. From a plane with a DSLR you will get the circular rainbows in the clouds that looks like your sample 3. Bright dot would be reflection and rainbow type more refraction.
 
Heiligenschein doe's do it but I don't think you can see the shadow of a P4 making the reflected light look brighter around a shadow when the craft may be 200 meters away and more, pretty small dot that I can't see at all. When this reflection happens I don't see any shadow at all just a circular bright dot, if the sun was square you would get a bright square (not a good one)
 
As explained in my original post, it's 100% not dust or anything.

The "glory"/"halo" explanation seems to be the answer. This is why our Drone Ranger hasn't been sent off for repair, as I've never been convinced it's a fault. And my considerable experience as a wildlife/landscape stills photographer (and occasional film maker in the pre-digital past) has never thrown this up, as I've been almost exclusively ground-based.

Thank you to those who've posted above for knowing the problem and working out what it's likely to be.

If anyone else can add anything further, it would be appreciated.
 
Am I correct in thinking that there's no way around this during golden hour, other than flying at a different angle - i.e. with the sun behind but a bit to the right or left - so that "The Blob" moves out of frame? This is what we did each time to get the good footage needed for the film being made, but it was annoying when options were limited because of some landscape specifically needed (and tricky with fast moving wildlife).
 
Am I correct in thinking that there's no way around this during golden hour, other than flying at a different angle - i.e. with the sun behind but a bit to the right or left - so that "The Blob" moves out of frame? This is what we did each time to get the good footage needed for the film being made, but it was annoying when options were limited because of some landscape specifically needed (and tricky with fast moving wildlife).
Unless the physics of light cease to apply at your location on Earth, then no, there's "no way around this".
 
Am I correct in thinking that there's no way around this during golden hour, other than flying at a different angle - i.e. with the sun behind but a bit to the right or left - so that "The Blob" moves out of frame? This is what we did each time to get the good footage needed for the film being made, but it was annoying when options were limited because of some landscape specifically needed (and tricky with fast moving wildlife).
Correct. No way around it other than don’t put the drone directly between the sun and your subject.
 
Correct. No way around it other than don’t put the drone directly between the sun and your subject.
So is this effect solely a function of the white color of the P4P, or does it happen equally with the Obsidian black version?
 
So is this effect solely a function of the white color of the P4P, or does it happen equally with the Obsidian black version?
Nothing whatsoever to do with the color of the drone. Have a look at the page linked to that talks about opposition surge. Here is a brief summary.

When filming irregular surfaces there will be some shadows on the surface (even very small ones) everywhere except where the light is reflecting directly back at you - no shadows there. That, by definition, is when the sun is right behind the camera. Everywhere else, the shadows (even small ones on rock or even grass) will average with the reflected light to an intensity less than that area where all light is reflected straight back with no shadows.

Hope that helps.
 

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