Akaso v50 Pro dropping frame rate

[hungaristani]

Hi, I made two approx. 90 minute recordings with identical settings on to the same SD card. 4K/30fps, Night mode ON, Stabilization ON. One recording was just fine, but the other one's effective frame rate was dropped to the quarter of the 30fps set in the menu, i.e. every four adjacent frames were identical, then followed by another cluster of 4 identical frames etc.
Does anyone have an idea what could be the reason for this?

[petesimon]

share a photo of your sd card(s). were you recording during the night, in low-light conditions?

i guess the camera can auto-adjust its frame rate and/or exposure in order to capture enough light in a dark scene. also, frame rates generally decrease in a dark scene. for example 1080p 60fps decreases to 30fps or even to 20 fps, and frames are duplicated once or twice, in a dark scene.

[hungaristani]

i guess the camera can auto-adjust its frame rate and/or exposure in order to capture enough light in a dark scene. also, frame rates generally decrease in a dark scene. for example 1080p 60fps decreases to 30fps or even to 20 fps, and frames are duplicated once or twice, in a dark scene.

Yes, I suspected something like that. It was a concert recording with constantly changing stage lights with some dark spots. The other recording was shot at the same stage next day, but in daylight (night mode was still ON). You wrote this is just a guess, so can someone confirm that night mode could actually drop the frame rate? Also it would be good to know how this works. The facts that next day's recording had full 30fps rate and that the first recording had a constant 7.5 fps effective rate through the entire recording (despite the changing lights) gives me the impression that the camera decides the frame rate to be used based on the lighting conditions at the beginning of the recording.