Camera log decode

_gg_ · Feb 1, 2022

Hi, my Phantom 4 started capturing too bright photos. I've found a solution here: Help. Images washed out (too bright) However, I would like to know what exactly happened. So, I've found that there are logs of camera parameters or something like that. Is there a way to decode them?

Meta4 · Feb 1, 2022

_gg_ said:
Hi, my Phantom 4 started capturing too bright photos. I've found a solution here: Help. Images washed out (too bright) However, I would like to know what exactly happened. So, I've found that there are logs of camera parameters or something like that. Is there a way to decode them?

Post one of the problem images and I'll see what the metadata shows.

_gg_ · Feb 1, 2022

Meta4 said:
Post one of the problem images and I'll see what the metadata shows.

Thanks, for the response. I've uploaded 2 images. DJI_0072.JPG, which is fine (Same drone, same day, same flight settings, almost same spot) and DJI_0073.JPG with a brightness issue.

Meta4 · Feb 2, 2022

_gg_ said:
Thanks, for the response. I've uploaded 2 images. DJI_0072.JPG, which is fine (Same drone, same day, same flight settings, almost same spot) and DJI_0073.JPG with a brightness issue.

Accidental setting of exposure compensation to override the camera's metering is the usual cause of unexpected under/over exposure.

Looking at the metadata from those two images, taken 16 minutes apart, shows that exposure compensation was set to zero for both, so that doesn't explain why DJI_0073 is significantly (2 stops) over exposed.

As both were shot using Program AE Mode, where the camera automatically chooses the exposure settings for you, it's not a case of you having set something incorrectly.

The exposure settings revealed in the image metadata are:

DJI_0072

ISO 100 1/320th sec F5.6 Exposure compensation = 0

DJI_0073

ISO 100 1/120th sec f4.5 Exposure compensation = 0

Why the camera chose those settings is a mystery, but that's why the exposure is so different.

Was this a one-off glitch or is it happening consistently?

_gg_ · Feb 2, 2022

Meta4 said:
Accidental setting of exposure compensation to override the camera's metering is the usual cause of unexpected under/over exposure.

Looking at the metadata from those two images, taken 16 minutes apart, shows that exposure compensation was set to zero for both, so that doesn't explain why DJI_0073 is significantly (2 stops) over exposed.

As both were shot using Program AE Mode, where the camera automatically chooses the exposure settings for you, it's not a case of you having set something incorrectly.

The exposure settings revealed in the image metadata are:

DJI_0072
ISO 100 1/320th sec F5.6 Exposure compensation = 0

DJI_0073
ISO 100 1/120th sec f4.5 Exposure compensation = 0

Why the camera chose those settings is a mystery, but that's why the exposure is so different.

Was this a one-off glitch or is it happening consistently?

It was a one-off glitch. These 16 min gap is due to that I had to change battery. All images before the change are like 72, and all after like 73. It sounds like a software glitch (I used Drone Harmony). What ISO 100 1/320th mean?

I've tried to recreate the error, but it never happened again

Meta4 · Feb 2, 2022

_gg_ said:
What ISO 100 1/320th mean?

The camera settings for the overexposed shot allowed 4 times as much light in as the settings for the shot with correct exposure

_gg_ said:
I've tried to recreate the error, but it never happened again

That's a good thing

_gg_ · Feb 2, 2022

Meta4 said:
The camera settings for the overexposed shot allowed 4 times as much light in as the settings for the shot with correct exposure

That's a good thing

Thanks for the help. It is a relieve that nothing is wrong with settings or drone. I guess, a sun light particle changed 1 bit and it resulted into this glitch.

Meta4 · Feb 2, 2022

_gg_ said:
Thanks for the help. It is a relieve that nothing is wrong with settings or drone. I guess, a sun light particle changed 1 bit and it resulted into this glitch.

A change in lighting wouldn't explain the issue.
The camera meter should adjust the camera settings to give correct exposure in any lighting conditions.
For some unknown reason, the camera's metering has made the incorrect camera settings.

MS Coast · Feb 2, 2022

_gg_ said:
It was a one-off glitch. These 16 min gap is due to that I had to change battery. All images before the change are like 72, and all after like 73. It sounds like a software glitch (I used Drone Harmony). What ISO 100 1/320th mean?

I've tried to recreate the error, but it never happened again

ISO is essentially the sensitivity setting for the photo sensor. Lower numbers give you better quality; higher numbers give you more sensitivity to light so you can shoot in lower light or with faster shutter speed or smaller aperture (higher f number). There was plenty of light, so the camera chose the lowest ISO setting to get the best image quality.

The 1/320 is the shutter speed, one 320th of a second.

Here's a good intro I dug up for a friend a few days ago.

https://www.masterclass.com/articles/photography-basics-what-is-exposure-understanding-how-exposure-affects-your-photographs

_gg_ · Feb 2, 2022

MS Coast said:
ISO is essentially the sensitivity setting for the photo sensor. Lower numbers give you better quality; higher numbers give you more sensitivity to light so you can shoot in lower light or with faster shutter speed or smaller aperture (higher f number). There was plenty of light, so the camera chose the lowest ISO setting to get the best image quality.

The 1/320 is the shutter speed, one 320th of a second.

Here's a good intro I dug up for a friend a few days ago.

https://www.masterclass.com/articles/photography-basics-what-is-exposure-understanding-how-exposure-affects-your-photographs

Thanks, the exposure is well explained there. I use images to get DTM, so all overexposed images should be discarded.