Black Screen -3.0 EV

[DPGaines]

Hello everyone,

I recently purchased a Mavic 2 Zoom, and about a month in I’ve noticed that the display screen on my phone becomes black with a -3.0 EV. I manually set all of my camera settings to ISO 100, Shutter Speed 1/50 (with ND Filter), proper white balance depending on the lighting, etc. I noticed that when I set the camera settings to auto, it increases the ISO to the maximum value, and the shutter to the minimum value, and the EV changes to -1.0, removing the lens cover (without flying obviously) also improves the lighting slightly. Has anyone else encountered this problem? I suspect that it might have something to do with the lens. I’ve never crashed it before, but I did fly it over the ocean (on a calm day) so could it be humidity related?

Thank you!

 

[Meta4]

I recently purchased a Mavic 2 Zoom, and about a month in I’ve noticed that the display screen on my phone becomes black with a -3.0 EV. I manually set all of my camera settings to ISO 100, Shutter Speed 1/50 (with ND Filter), proper white balance depending on the lighting, etc. I noticed that when I set the camera settings to auto, it increases the ISO to the maximum value, and the shutter to the minimum value, and the EV changes to -1.0, removing the lens cover (without flying obviously) also improves the lighting slightly.

If you have manual exposure set and the screen display is showing EV -3.0, that's the camera meter telling you that your camera settings are at least 3 stops under exposed, which explains why the screen is very dark.

If you have EV -1.0 showing when on auto-exposure, that's indicating that you have set the camera to underexpose by 1 stop.

In auto, dial the exposure compensation back to EV0.
Then try setting the camera to aperture exposure mode A, ISO to 100 and see how that looks outdoors.

 

[Facious]

Does it go totally black, or just the camera live view is very dark? And what happens if you set the exposure compensation to zero? Since you say you are using manual mode, the EV value shows you how your photo/video will look like in relation to correct exposure (-3EV is heavily underexposed, which means there's not enough light for the settings you want to use). Have a read here, this explains exposure compensation: What is Exposure Compensation and How to Use It

 

[MAvic_South_Oz]

What grade ND filter ? (4,8,16, etc)
Do you have a set of these and adapt to the approx daylight conditions ? (Before altering other settings.)
Have you been finding these problems anytime during the day, or at a specific early / late time ?

removing the lens cover (without flying obviously) also improves the lighting slightly

Are you talking about the ND filter ?

What happens when you remove any filter, put camera to full auto ?

 

[gnirtS]

Theres not enough light.

You really really need to read about what an exposure is and what makes it up rather than just dialling random settings you read on the internet.

You cant just dial in random numbers and expect the image to by exposed correctly as if by magic.

 

[DanMan32]

I think he means the stock UV filter.

 

[DPGaines]

If you have manual exposure set and the screen display is showing EV -3.0, that's the camera meter telling you that your camera settings are at least 3 stops under exposed, which explains why the screen is very dark.

If you have EV -1.0 showing when on auto-exposure, that's indicating that you have set the camera to underexpose by 1 stop.

In auto, dial the exposure compensation back to EV0.
Then try setting the camera to aperture exposure mode A, ISO to 100 and see how that looks outdoors.

I can achieve an exposure of 0 now when I let the drone automatically control the ISO and Shutter Speed Values, but the values seem way off to me. For instance in a well lit indoor environment, my ISO is at 400 and shutter speed at 1/15. I used to be able to get a clear display with my manual settings. These don’t even have ND Filters either, adding the filters makes the images hopelessly dark.

 

[DPGaines]

What grade ND filter ? (4,8,16, etc)
Do you have a set of these and adapt to the approx daylight conditions ? (Before altering other settings.)
Have you been finding these problems anytime during the day, or at a specific early / late time ?



Are you talking about the ND filter ?

What happens when you remove any filter, put camera to full auto ?

I was using the stock filter, but I tested with ND filters as well and the images were even darker as expected. The ISO and Shutter Speed required even more extreme adjusting. If you look at the photos I posted above, those were also with the stock UV filter on a decent lit cloudy day.

 

[DPGaines]

Theres not enough light.

You really really need to read about what an exposure is and what makes it up rather than just dialling random settings you read on the internet.

You cant just dial in random numbers and expect the image to by exposed correctly as if by magic.

There is enough light, and I am well aware of the the relationship between ISO, aperture, and shutter speed. I’ve done lots of videos with the manual settings, and one day the screen just went dark. You should never need to increase the ISO above 100 on a sunny day. I have lots of videos with similar lighting using manual settings, I think that’s enough to rule out low lighting.

 

[Meta4]

I can achieve an exposure of 0 now when I let the drone automatically control the ISO and Shutter Speed Values, but the values seem way off to me. For instance in a well lit indoor environment, my ISO is at 400 and shutter speed at 1/15. I used to be able to get a clear display with my manual settings. These don’t even have ND Filters either, adding the filters makes the images hopelessly dark.

If your camera is giving proper metering and you have a clear display with auto exposure settings, then it should with manual settings ... as long as your manual settings are appropriate for the scene and lighting.
Are your two example shots in the same place/same lighting? (If it's not, it's of no use as a comparison).
If so, it's obvious that your manual setting of ISO 100 1/50th is woefully underexposing that scene (although it might be fine outdoors in better light).
ISO 100 @ 1/50th is about 4 stops lower than ISO 400 @ 1/15th.
That means those settings are reducing the light by about 94% which would explain your dark screen.

 

[gnirtS]

. You should never need to increase the ISO above 100 on a sunny day. I have lots of videos with similar lighting using manual settings, I think that’s enough to rule out low lighting.

No its not. If the EV is showing -3 and a black screen its off-scale low under exposed. So its a black image. So there isnt anywhere near enough light by at LEAST 3 full stops.

You cant just randomly dial in the settings you want and it'll magically be correctly exposed.

The light level is low, you're grossly under-exposing. The drone is telling you that. You need to change your exposure settings.

 

[DPGaines]

No its not. If the EV is showing -3 and a black screen its off-scale low under exposed. So its a black image. So there isnt anywhere near enough light by at LEAST 3 full stops.

You cant just randomly dial in the settings you want and it'll magically be correctly exposed.

The light level is low, you're grossly under-exposing. The drone is telling you that. You need to change your exposure settings.

ISO is always supposed to be 100 unless you’re in incredibly low light (past sunset). Any higher and you will get noise in your videos. The shutter speed is supposed to be approximately double the frame rate to produce the appropriate amount of motion blur in your videos to look natural (24 FPS = 1/50 shutter speed). Normally 1/50 shutter speed grossly overexposes a shot making it too bright, that’s why Neutral Density Filters are needed for shooting high quality videos. Even when it’s cloudy, you still need an ND4 filter to correct the overexposure.

1/50 shutter speed and 100 ISO should NEVER underexposed a shot, especially 3 stops. I took those two photos above on a cloudy day without an ND Filter (I used original UV filter that came with the drone) and it was underexposed 3 stops as you can see. What I’m saying is that under exposure should not happen period, and I contacted DJI support and they also confirmed that this was abnormal as well. That’s why I’m on here trouble shooting in the first place.

These are not random settings that I plugged in for no reason, these are standard values that drone pilots need to shoot at in order to get high quality videos.

 

[DPGaines]

If your camera is giving proper metering and you have a clear display with auto exposure settings, then it should with manual settings ... as long as your manual settings are appropriate for the scene and lighting.
Are your two example shots in the same place/same lighting? (If it's not, it's of no use as a comparison).
If so, it's obvious that your manual setting of ISO 100 1/50th is woefully underexposing that scene (although it might be fine outdoors in better light).
ISO 100 @ 1/50th is about 4 stops lower than ISO 400 @ 1/15th.
That means those settings are reducing the light by about 94% which would explain your dark screen.

What I’m trying to figure out is why the ISO needs to be at 400 and shutter speed at 1/15th in the first place. Some research that I’ve done and responses from DJI support have indicated that those values are very abnormal. I’ve shot footage in even less lighting than when I took those pictures, and normally I would need an ND4 filter at the minimum to correct over exposure.

My current theory is that something may be blocking light from getting into the lens (dust particles or something). The next thing that I will try is to clean the internal lens with an appropriate lens cleaner.

 

[gnirtS]

ISO is always supposed to be 100 unless you’re in incredibly low light (past sunset).

No its not. Go and read up what ISO actually is.

[quote[
Any higher and you will get noise in your videos.[/quote]

You get noise at all ISOs. It merely increases as ISO goes higher.

The shutter speed is supposed to be approximately double the frame rate to produce the appropriate amount of motion blur in your videos to look natural (24 FPS = 1/50 shutter speed).

Its a guide not a rule. Its also not always possible.

Normally 1/50 shutter speed grossly overexposes a shot making it too bright, that’s why Neutral Density Filters are needed for shooting high quality videos. Even when it’s cloudy, you still need an ND4 filter to correct the overexposure.

Not always you dont. Its perfectly possible to under expose a shot at ISO100 and 1/50th especially if using narrow apertures.

These are not random settings that I plugged in for no reason, these are standard values that drone pilots need to shoot at in order to get high quality videos.

There is no such thing as a "standard value" exposure. That merely highlights your lack of understanding about the whole exposure triangle if nothing else.

 

[DPGaines]

The aperture of the Mavic 2 Zoom is fixed to F/2.8 at 24 mm (adjusts slightly during zooming though). I’ve seen that referred to as a large/wide aperture on most websites. I understand that ISO 100 and 1/50 shutter speed can underexposed a narrow aperture shot, but fixed aperture DJI drones do not have narrow apertures. I used those manual settings the first day I flew the drone, and only adjusted the shutter speed when changing frame rates. Never had to adjust ISO above 100 once for two months, no matter what the lighting environment was (sunrise, sunset, incandescent lights, cloudy day, sunny day, etc). It’s also important to note that it is illegal to fly a drone without an FAA waiver 30 minutes before sunrise and 30 minutes after sunset, so I’ve never flown in a super low lighting environment (that would definitely require shifting ISO and shutter speed). I also don’t fly my drone when there isn’t enough light for the vision obstacle sensors to function properly, and it gives you a warning if that’s the case. I only had to adjust ND filters to correct exposure (ND4 sunrise/sunset/dark clouds, ND8 bright clouds, ND16 sunny, and ND32 very bright sun) and it would always land within .3 stops of zero. I understand that most cameras do not have a standard shutter speed value, but with fixed aperture DJI drones (most have the same fixed aperture value) that shutter speed guide (double the frame rate) is highly recommended by most professional pilots who make cinematographic videography, unless filming fast paced sports or purposely creating large amounts of motion blur.