1080x120 in apps

[nhoover]

I noticed a really strange thing today. I see on DJI's spec page that the options for video for the P4 are:

UHD: 4096×2160 (4K) 24 / 25p
3840×2160 (4K) 24 / 25 / 30p
2704×1520 (2.7K) 24 / 25 / 30p
FHD: 1920×1080 24 / 25 / 30 / 48 / 50 / 60 / 120p
HD: 1280×720 24 / 25 / 30 / 48 / 50 / 60p

I was pretty sure we never had 120p so I fired up the P4 to check. I was amazed to see the 120p option for 1080 video both in Litchi and DJI Go. I tried shooting a quick sample in all the 1080 settings and see:

Setting, actual frame rate, approx bitrate
24p, 24 fps, 25mbps
30p, 30 fps, 40mbps
48p, 48 fps, 40 mbps
60p, 60 fps, 60 mbps
120p, 30 fps, 12.5 mbps - and it is 1080 not 720.

I repeated the tests with both Litchi and Go - identical. I've just this week upgraded my Nexus 9 tablet to Android 7. I doubt that's it, but what is going on here? I thought it was up to 60p in 1080 and 120p only in 720.

DJI spec is here: DJI Phantom 4 – Specs, FAQ, Tutorials and Downloads

 

[Jussaguy]

I noticed a really strange thing today. I see on DJI's spec page that the options for video for the P4 are:

UHD: 4096×2160 (4K) 24 / 25p
3840×2160 (4K) 24 / 25 / 30p
2704×1520 (2.7K) 24 / 25 / 30p
FHD: 1920×1080 24 / 25 / 30 / 48 / 50 / 60 / 120p
HD: 1280×720 24 / 25 / 30 / 48 / 50 / 60p

I was pretty sure we never had 120p so I fired up the P4 to check. I was amazed to see the 120p option for 1080 video both in Litchi and DJI Go. I tried shooting a quick sample in all the 1080 settings and see:

Setting, actual frame rate, approx bitrate
24p, 24 fps, 25mbps
30p, 30 fps, 40mbps
48p, 48 fps, 40 mbps
60p, 60 fps, 60 mbps
120p, 30 fps, 12.5 mbps - and it is 1080 not 720.

I repeated the tests with both Litchi and Go - identical. I've just this week upgraded my Nexus 9 tablet to Android 7. I doubt that's it, but what is going on here? I thought it was up to 60p in 1080 and 120p only in 720.

DJI spec is here: DJI Phantom 4 – Specs, FAQ, Tutorials and Downloads

Odd. I think you just discovered a typo.

It does indeed say "120p" but it means "FPS".

It lists all the different resolutions and the frame rates available at those resolutions.

At 1080p (1920x1080) there are several frame rates available, they are 24, 25, 30, 48, 50, 60 and 120 FPS. Not sure what the p is there for. 1080p means "progressive" vs 1080i "interlaced" and the 120fps is an attempt to create a slow motion option.

Unfortunately, it ain't that great of a slow mo.

 

[jwt873]

Yes, the P appears to be misplaced .

On page 57 of the User manual it says: "

In addition to lens improvement the camera firmware has been tweaked to enable the camera to capture 120fps video in full 1080p FHD (the camera's field of view will be reconfigured to 47 degrees when recording in this mode) for smooth slow motion".

So it is correctly identified as FPS there....

 

[With The Birds]

Would be good if while "tweaking the firmware" Dji could fiddle with the bitrate. The Ambarella A9 can do 240 Mbp/s @ 4K- why they limit us to 60 makes no sense.

 

[jason]

Gee my new camera can shoot 1080p at 240. 480 and 960 fps which is a blast.

 

[With The Birds]

Gee my new camera can shoot 1080p at 240. 480 and 960 fps which is a blast.

sounds impressive. Not so exciting when you look at the full story and consider its not native 1080, it will be 800 by 270 up scaled. You should get 1000fps in PAL also. Still very cool though.

 

[jason]

sounds impressive. Not so exciting when you look at the full story and consider its not native 1080, it will be 800 by 270 up scaled. You should get 1000fps in PAL also. Still very cool though.

Look at the Sony rx10 ii. Those frame rates are called HFR and the clips are converted to 1080p in camera. It also shoots 4K@ 3840 x 2160 and 1080p@120, 60 and 30fps while shoots 720p@30fps only.

GoPro hero 4 black can shoot 1080p@120, 90, 80, 60, 48, 30 and 24fps. In 720p@ 240, 120, 60 and 30fps

There is no camera that can do everything.

 

[With The Birds]

Look at the Sony rx10 ii. Those frame rates are called HFR and the clips are converted to 1080p in camera. It also shoots 4K@ 3840 x 2160 and 1080p@120, 60 and 30fps while shoots 720p@30fps only.

GoPro hero 4 black can shoot 1080p@120, 90, 80, 60, 48, 30 and 24fps. In 720p@ 240, 120, 60 and 30fps

There is no camera that can do everything.

That is the camera i had a breif chance to play with, i think it does 100 Mbp/s also at 4k. I wish DJI would give us more than 60, the hardware is seeminly capable of 240 looking at the hardware spec.

 

[jason]

Yes the RX10 ii do shoot 4K@100m. how about shooting 4K @ 1/4 f at night unbelievable at high ISO with very low noise. Plus the full zoom feature while shooting video. There are not any still/video cameras that can zoom in/out while shooting video it's like having camcorder. I've been working on the house all summer and haven't had the time to fly let alone do much camera work either and I do have a few to many cameras.

 

[ussvertigo]

I used the 120fps function for a scene in a video I put together with rest of video shot in 4K, though final version output from PremProCC was in 1080p, that scene was neat, but quality was obviously not so good, even more so when output set at 4K.
What I would like to know is when one would use 1080p 60fps vs 30fps, examples would be appreciated.

 

[Jussaguy]

Would be good if while "tweaking the firmware" Dji could fiddle with the bitrate. The Ambarella A9 can do 240 Mbp/s @ 4K- why they limit us to 60 makes no sense.

Makes perfect sense.

They want to keep the price down so they make it so that we can use MicroSD cards which most people can barely get to 40-60.

If you record at above what you can write, you get what you can write. So in an effort to keep the price down, and because it's not a pro cam, nor is the Amberella A9 which also shoots h.264 and since it also records with micro sd cards, it will be bottle necked at the speed of the card.

If you want a non h.264 codec and faster bit rate, get an x5r, and it has the SSD 500mbps vs the 30-95 you'll get from the MicroHD cards. It'll cost you a couple grand more but you'll get what you want.

 

[With The Birds]

Makes perfect sense.

They want to keep the price down so they make it so that we can use MicroSD cards which most people can barely get to 40-60.

If you record at above what you can write, you get what you can write. So in an effort to keep the price down, and because it's not a pro cam, nor is the Amberella A9 which also shoots h.264 and since it also records with micro sd cards, it will be bottle necked at the speed of the card.

If you want a non h.264 codec and faster bit rate, get an x5r, and it has the SSD 500mbps vs the 30-95 you'll get from the MicroHD cards. It'll cost you a couple grand more but you'll get what you want.

Im not a pro shooter, h.264 is fine for my purposes. The data rate is the frustrating dissapointment. I think we way be confusing MB's and Mb here. Current UHS1 cards, even the lower specced ones easily support 100 Mb/s (13MB/s).