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Possible Lens Contamination

Axxa

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I noticed the appearance of "cells" on the attached photo shot w/my Mavic Pro this afternoon. I read somewhere that I might have a lens contaminated by dust or dirt on the back side of the lens cover.
I went back and looked at photos taken last year and I see the "cells" on those photos as well. They appear more prominently in less busy areas of the pix, like skies. Interestingly, the "cells" are in the same position on all photos.
Can anyone confirm if my lens is in fact contaminated or is it experiencing some other situation? And possibly suggest a remedy?
Thanks...
 

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And possibly suggest a remedy?
Looks like the problem is optical rather than a faulty sensor etc.
You can get an idea of the extent of it by shooting a whole frame of something light like a house wall.
 
The file I offered in my original post was shot after cleaning the lens...and the filter.
Today I shot a blank surface, with and w/o a filter and the "cells" are still present. They seem to be located in the top 1/4 of the frame, reaching from left to right margins. As in all photos that I've seen the apperitions or "cells", they are all in the same place.
Also, the "cells" are evident only after I attempt to adjust exposure, contrast and highlights in either Adobe Lightroom CC or PS CC. Otherwise, in an unedited photo, they are not present.
 
The spots do look more like on a lens than on a sensor. Sometimes you can not easily see such spots on a lens, even after cleaning, but adjusting settings in post makes them appear. How have you been cleaning your lens, as in with what?
 
Before I discovered the "cells", I used 2-3, 1sec, soft canned air bursts and a lens brush. After it occurred to me that the "cells" might be water drop stains, I used a liquid lens cleaner applied to a micro fibre cloth, then wiping the lens in a circular motion.
 
Yes that would be the correct way beginning in the centre and working your way out to the edges.
 
I’m in the other school of thought. I think you will find it is a sensor defect. I think it’s in the passivation on the CMOS sensor and went undetected at the foundry through assembly. The size of the “bubble” artifacts would be small enough to be missed by most inspection methods.
Just my 2 cents
Good luck
I would contact DJI to see if they have heard of or detected it in other devices
 
If several proper attempts at cleaning the lens has not even phased the bubble artifacts, then you may well be correct in the assumption that this is on the actual sensor. They just don't look like the usual spots you get when a sensor needs cleaning, like on a DSLR, since they overlap each other.
 
I dropped off the drone at a DJI store yesterday for forwarding to a repair center. I showed the guys at the store a still of the problem and they admitted to not having seen the problem before. I'll get a determination from the techs at the repair center in about a week.
 
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I dropped off the drone at a DJI store yesterday for forwarding to a repair center. I showed the guys at the store a still of the problem and they admitted to not having seen the problem before. I'll get a determination from the techs at the repair center in about a week.
Let us know the outcome, this is an interesting delemia.
 
Sooooooo...I finally heard from the NY DJI Tech center after 7 long days. I received an email asking me to accept or deny their determination that a refurbished gimbal and camera would rectify my problem. The email also included an estimate of how much it would cost and how long it would take to replace and ship. That was it. No results on what their investigations found.
They listed a phone number for the tech center if I had any questions. I did. I called the number and spoke to a technician. I gave him my case # and he pulled up my file. They were able to replicate the "cells" that I was experiencing and felt confident that the sensor was at fault. I asked what could cause the sensor to go bad. His response was that flying near water (no, not really close), landing in a sandy, dusty area (OK, did that a few times), flying in misty conditions (nope) or crashing (yep, did that once) would all be situations that could damage a sensor.
I'm going to get the drone repaired, use it for the rest of the season and then put it up for sale. Other than that 1, 10' drop from a tree branch (my one crash), the unit has been meticulously cared for and maintained. I really like the MA and the M2 Zoom.
Anyway, thanks to everyone who responded for your interest and input.
 
Water spots on a front lens would actually never be visible - at worst you would have a slight reduction in image contrast with a dirty front element. With a DSLR lens, for example, you can literally cut out a little piece of paper and tape it to the lens and you won't see it in the photo if the focus plane is distant. Spots/debris on a lens' rear element are a different story and much worse.

That actually looks similar to oil on a sensor, but that is highly unlikely given the size of the circles and that the M2P does not have a mechanical shutter. If the aperture mechanism is oiled, it's possible it's from that but it looks more like weird flare to me - the spots are too big to be oil.

Looks to me like unusual lens flare, especially since it only occurs in the highlight area. A defective sensor (i.e. some sort of electronic or manufacturing fault) would never look like that. Does it happen all the time or just when shooting into the sun? In your sample photo the sun looks like it's just outside the frame, which is the perfect recipe for flare.

The repair person's responses to your question of "what makes a sensor go bad" tell us they have absolutely no idea what they're talking about. None of those things listed would ever damage the sensor under normal circumstances except possibly crashing, and physical sensor damage would not manifest itself like the flare rings in your image. If anything I'd bet your crash impact decentered some of the lens elements allowing for an unusual flare situation when presented with a bright condition. I would bet money that the actual image sensor is 100% fine.
 
This is an M1P, not an M2P, correct? Some seem to be getting confused about that.
Have you conversed with ThunderDrones? He might be able to replace the sensor rather than the entire gimbal.
 
Yes DanMan32, you are correct...it is an MP1. Also, I have not been in touch w/ThunderDrones. I did not think to do so in my haste to get the drone into DJI's system for repair.
You make some good points CanadaDrone. As I've accepted DJI assessment of the problem and authorized their recommendation, we will never truly know what the problem was. I asked the tech if they could simply fix my camera or replace a faulty sensor and his response was no. All they can do it seems, for camera issues, is to replace them with refurbished units. If I wanted my camera to be repaired, the unit would need to be shipped to China.
As you would expect, I will thoroughly test the camera when the drone is returned and report my findings.
 
Found your thread trying to find information about those spots. I have two of them I noticed on my last trip out. Cleaned the lens as well as the polarizer - even removed it to see if that was the problem. No luck.
 
Ok my 2 cents. That looks like dust on your sensor! Why do I think that? I somehow got moisture in my camera so after many attempts at trying to dry it out by removing the camera placing it in a silica gel box etc etc I figured I had nothing to lose by tapping the glass with a center punch removing it then replace it with one of my filters I use when flying. Did that but it seems that very fine particles of dust managed to find their way into the camera when I blew it off after removing the glass.
The result was EXACTLY the same as what I see in your pic! Finally ended up replacing the camera & it is perfect.
Good luck
 
Ok my 2 cents. That looks like dust on your sensor! Why do I think that? I somehow got moisture in my camera so after many attempts at trying to dry it out by removing the camera placing it in a silica gel box etc etc I figured I had nothing to lose by tapping the glass with a center punch removing it then replace it with one of my filters I use when flying. Did that but it seems that very fine particles of dust managed to find their way into the camera when I blew it off after removing the glass.
The result was EXACTLY the same as what I see in your pic! Finally ended up replacing the camera & it is perfect.
Good luck

Ugh... I was hoping not having to need a camera replacement. DJI needs to do a better job sealing the sensor.
 
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