Hi dears.
I crashed my P4 pro 5 months ago.and sent it to DJI service center to restore.  I thought they fixed my drone as well. Replaced whole covers  tripods,  sensors, tripod and gimbals.
After I received my drone,  I recorded a footage and video has so many sports like water drop or some thing like this.   I couldn't see any spots or scratches on my camera lens.
but  footage has spots....  How can I fix this ...

Item        Quantity        Unit Price（CNY）        Total Price（CNY）
Phantom 4 2312S Motor        1        110.00        110.00
Upper Cover (Logo) V03        1        40.00        40.00
Left Landing Gear Module        1        60.00        60.00
Middle Frame        1        127.00        127.00
Phantom 4 Yaw-axis Motor V2        1        75.00        75.00
Roll-axis Bracket        1        38.00        38.00
Gimbal Yaw-axis & Roll-axis ESC Board        1        92.00        92.00
Battery Compartment Module        1        131.00        131.00
Pitch-axis Bracket V03        1        44.00        44.00
Pitch-axis Motor        1        75.00        75.00
Gimbal Vibration Absorbing Board        1        3.00        3.00
Yaw-axis Motor Cable Cover        1        2.00        2.00
Phantom 4 Roll Motor        1        75.00        75.00
Lens Front Shell (With Shielding Cover)        1        79.00        79.00
Gimbal Flexible Flat Cable (Long)        1        92.00        92.00
Right Landing Gear Module        1        60.00        60.00
Repair Service Fee        2        60.00/H        120.00
Freight:                        0.00
Total Amount:                        1223.00
Discount:                        -0
DJI Care deduction:                        0.00
Total Payment:                        1223.00

I thought they fixed my drone as well. but i got a spot on my footage...

I wonder if it may be dirt on the camera sensor if you can see no outside signs of contamination. They look very similar to having problems with a DSLR.

Hi enkhtaivan, sorry for the troubles, like embayweather mentioned, there may be dirt on the lens and we cannot see obviously, please clean the lens via cotton swab to have a try.

Did you unscrew the lens filter and clean the actual lens inside?

DJI Mindy Posted at 2018-5-8 04:41
Hi enkhtaivan, sorry for the troubles, like embayweather mentioned, there may be dirt on the lens and we cannot see obviously, please clean the lens via cotton swab to have a try.

cleaned so many times. and then taught there is a dust inside of glass...

Anokadrone Posted at 2018-5-8 08:39
Did you unscrew the lens filter and clean the actual lens inside?

No, didn't try.  just from outside. Is it possible to unscrew the lens filter ?  even so how?

if you are on about the uv filter then lick 1st 2 fingers and thumb, then ever to gently hold the lens with fingers and thumb in equal 3rds on the lens and unscrew, if it does not move then you are gripping too tighly, keep equal pressure between fingers and thumb and unscrew, the touch needs to be so light that your fingers are hardly touching it, the lighter the touch the better it will unscrew, its made of plastic so any uneven pressure will cause it to grip the thread and make it near on impossible to unscrew...

Bashy Posted at 2018-5-8 20:22
if you are on about the uv filter then lick 1st 2 fingers and thumb, then ever to gently hold the lens with fingers and thumb in equal 3rds on the lens and unscrew, if it does not move then you are gripping too tighly, keep equal pressure between fingers and thumb and unscrew, the touch needs to be so light that your fingers are hardly touching it, the lighter the touch the better it will unscrew, its made of plastic so any uneven pressure will cause it to grip the thread and make it near on impossible to unscrew...

thanks I will try and reply later.

Bashy Posted at 2018-5-8 20:22
if you are on about the uv filter then lick 1st 2 fingers and thumb, then ever to gently hold the lens with fingers and thumb in equal 3rds on the lens and unscrew, if it does not move then you are gripping too tighly, keep equal pressure between fingers and thumb and unscrew, the touch needs to be so light that your fingers are hardly touching it, the lighter the touch the better it will unscrew, its made of plastic so any uneven pressure will cause it to grip the thread and make it near on impossible to unscrew...

Just curious as to whether you got in there and if that worked?

enkhtaivan Posted at 2018-5-8 16:58
cleaned so many times. and then taught there is a dust inside of glass...

Sorry for the late response, if the issue persists, I'm afraid the drone will need to be sent in again for evaluation.

DJI Mindy Posted at 2018-5-15 00:52
Sorry for the late response, if the issue persists, I'm afraid the drone will need to be sent in again for evaluation.

Is there any need to pay more fee for service again?  Service also shipping.
Why you guys sent it back without testing all of parts? Specially after  replacing camera body parts!!!
I thought your guys didn't work carefully when replacing Lens Front Shell (With Shielding Cover) ...

More details please check VIA this service tag number CAS-897480-H9B9V2

enkhtaivan Posted at 2018-5-29 22:27
Is there any need to pay more fee for service again?  Service also shipping.
Why you guys sent it back without testing all of parts? Specially after  replacing camera body parts!!!
I thought your guys didn't work carefully when replacing Lens Front Shell (With Shielding Cover) ...

We do apologize for the unpleasant experience with our repair center, the drone should have been tested before shipping out. Since the drone was repaired on 2017/8/30, it has been a long time before you report the issue, we will need to make a damage assessment to locate the problem, please contact our support team to start a ticket here: https://www.dji.com/cn/support?site=brandsite&from=nav

Resolved the problem after 2 years later .
Just kept my drone in storage during these time without using () ...
Now it has super clean image. Opened up my  camera back and cleaned sensor with soft towel and put it back...
there was a oil spot on sensor :p . Know I'm using every weekend ...

I've read several  posts on the web and watched YouTube regarding removal of the  lens cover for the  camera apparently  they use thread lock  on the threads  making it  impossible to remove the cover  or cause damage  or compromise  the threads. The post before that said ever so gently  turn the cover? NO, that dosen't work at all,  so what ape in the assembly line  put my cover on because now my threads are messed up. My polar pro  filters  go on but I have to be very careful  to save what threads are left.  Such a stupid method dji did ridiculous.