Hi,

Just purchased an Osmo Action 4 and really couldn't be more stoked on it. I primarily use this for POV footage of my mountain biking and with a few quick google searchs I was able to find some solid settings that work best for me so far but I'm looking to further that.

Currently, I've been loving the native vertical shooting mode with the use of the horizon balance stabilization for social media. I think the effect this has looks really good with mountain biking where you can see how tilted the bike gets in the corners. My only issue with this is how cropped the video becomes. I've played with some other stabilization settings like the rocksteady and rocksteady+ but my issue with the rocksteady is that it isn't steady enough for the DJI chest mount that I have. It bounces too much through rock gardens and the footage becomes unusable (I purchased a chinmount for my full face helmet and will try that out too as I've heard it will keep the camera more stable but I'm unsure about how well it will work with the camera in the vertical/portrait orientation).

My question here is, what is the crop with the different stabilizations and FOV's? I saw somewhere in these forums that claimed the wide and ultrawide were wider angles than the standard (dewarp) but with a quick test in my living room it was obvious that I had the widest range of view in the standard (dewarp) in the vertical orientation. I'm curious if there are some actual numbers that we can put to this so that I can find the widest angle in vertical/portrait orientation while keeping my footage stabilized.

Can someone please help me?

Thanks

Have a look into this thread:
https://forum.dji.com/forum.php? ... p;page=1#pid3104717
DJI Gamoro wrote:
Hi, fans386d0668. Thank you for reaching out. The frame may be cropped according to the lens or stabilization mode. For example, in "4K/4:3" mode:
1) If the "FOV" is set as "Wide", the DFOV is 155 (with EIS disabled) or 140 (with RockSteady enabled).
2) If the "FOV" is set as "Standard (Dewarp)", the DFOV is 126 (with EIS disabled) or 116 (with RockSteady enabled).
3) If the "FOV" is set as "Ultrawide", the DFOV is 155 (with EIS disabled) or 146 (with RockSteady enabled). For the drop in resolution from 4K, hopefully, other users can provide their insights on that.

Helmut Ruch Posted at 10-27 00:38
Have a look into this thread:
https://forum.dji.com/forum.php?mod=viewthread&tid=295310&page=1#pid3104717
DJI Gamoro wrote:

Yes, I've seen that but I guess I'm hoping to get more info on the crop factors of rocksteady + and Horizon balancing as well. After playing around with the camera last night I found that these numbers are seemingly true for rocksteady. With rocksteady+ though, the widest seeming angle is standard dewarp. For whatever reason it doesn't crop as much as wide does which I find a little odd.

lewlewland Posted at 10-27 08:50
Yes, I've seen that but I guess I'm hoping to get more info on the crop factors of rocksteady + and Horizon balancing as well. After playing around with the camera last night I found that these numbers are seemingly true for rocksteady. With rocksteady+ though, the widest seeming angle is standard dewarp. For whatever reason it doesn't crop as much as wide does which I find a little odd.

In the last message in the linked threat you find the following statement of another DJI-Official:

For those crop ratio are high, say horizonsteady(20mm) or narrow (24mm), Action4 only provides 2.7k, because it can never upscale to 4K look.

Helmut Ruch Posted at 10-27 10:36
In the last message in the linked threat you find the following statement of another DJI-Official:

For those crop ratio are high, say horizonsteady(20mm) or narrow (24mm), Action4 only provides 2.7k, because it can never upscale to 4K look.

I might just not be understanding but I'm hoping to get the angle degrees for the other stabilizations similar to how @DJI Gamor wrote for Rocksteady

Helmut Ruch Posted at 10-27 00:38
Have a look into this thread:
https://forum.dji.com/forum.php?mod=viewthread&tid=295310&page=1#pid3104717
DJI Gamoro wrote:

I wished DJI allowed the saving of Gyrodata in 4:3 ultrawide, with EIS off, so I could stabilize it myself in Gyroflow and maintain the widest possible field of view.

I use ND filters when it is on my FPV drone, so I can't use any of the camera's stabilization modes there.

Anonymous1 Posted at 10-28 09:57
I wished DJI allowed the saving of Gyrodata in 4:3 ultrawide, with EIS off, so I could stabilize it myself in Gyroflow and maintain the widest possible field of view.

I use ND filters when it is on my FPV drone, so I can't use any of the camera's stabilization modes there.

Ultra Wide and Wide with Rocksteady turned off in 4:3 ratio have the same 155 degree FOV.
So we already have the widest possible for gyro stabilization.

johansenfoto Posted at 10-28 14:53
Ultra Wide and Wide with Rocksteady turned off in 4:3 ratio have the same 155 degree FOV.
So we already have the widest possible for gyro stabilization.

Is "Wide" also using the same sensor area as ultra-wide?

Anonymous1 Posted at 10-28 16:04
Is "Wide" also using the same sensor area as ultra-wide?

Without stabilization (Rocksteady), yes.

lewlewland Posted at 10-27 08:50
Yes, I've seen that but I guess I'm hoping to get more info on the crop factors of rocksteady + and Horizon balancing as well. After playing around with the camera last night I found that these numbers are seemingly true for rocksteady. With rocksteady+ though, the widest seeming angle is standard dewarp. For whatever reason it doesn't crop as much as wide does which I find a little odd.

Hi, lewlewland. Thank you for reaching out. When the camera is in Ultra Wide mode, it is necessary to lower the resolution and frame rate. When recording videos in the following formats, Ultra Wide mode is not supported:
1080p 100/120/240
2.7k (16:9) 100/120
4k (16:9) 100/120

DJI Gamora Posted at 10-29 07:59
Hi, lewlewland. Thank you for reaching out. When the camera is in Ultra Wide mode, it is necessary to lower the resolution and frame rate. When recording videos in the following formats, Ultra Wide mode is not supported:
1080p 100/120/240
2.7k (16:9) 100/120

I'm sorry but this is not what I'm looking for. Can you please give me the degrees of FOV with rocksteady in ultrawide at 16:9 and 4:3? Could you also let us know what the degrees of FOV are with rocksteady+ and horizon balance?

It would be awesome if there was a chart that had all of these numbers in it

lewlewland Posted at 10-30 08:27
I'm sorry but this is not what I'm looking for. Can you please give me the degrees of FOV with rocksteady in ultrawide at 16:9 and 4:3? Could you also let us know what the degrees of FOV are with rocksteady+ and horizon balance?

It would be awesome if there was a chart that had all of these numbers in it

Hello, lewlewland. We are sorry to inform you that there is no more information that can be found/no information about the degrees of FOV with rocksteady in ultrawide at 16:9 and 4:3 and degrees of FOV with rocksteady+ and horizon balance. Could you kindly tell us what problems you encounter during use? And we can help you solve it. Thank you for your kind understanding.

DJI Gamora Posted at 11-3 04:15
Hello, lewlewland. We are sorry to inform you that there is no more information that can be found/no information about the degrees of FOV with rocksteady in ultrawide at 16:9 and 4:3 and degrees of FOV with rocksteady+ and horizon balance. Could you kindly tell us what problems you encounter during use? And we can help you solve it. Thank you for your kind understanding.

I'm not encountering any issues necessarily. I'm just trying to find the widest angles in each aspect ratio and stabilization modes

What I understand is that just like GoPro, the camera uses the full sensor at all times (once not using De-warp).   What really changes is the fish-eyed look.

GoPro does ~10% crop in each increment of stabilization you enable.   I feel DJI does 10% crop first, then an additional 5% for Rocksteady+

Someone answered your specific question in a YouTube review months ago with actual figures based on actual experiments.  You can draw a large protractor on the ground, or mount the Action 4 on a tripod and have some known measurements with trigonometry.  I believe this is why GoPro uses 5K and 5.3K sensors for the crop factor when recording in 4K.

DJI upscales the cropped and stabilized image to fit the 4K resolution.  You could with editing software roughly find out yourself by recording an unstabilized still video 1 second long on a tripod, then another stabilized video for another second in the stabilization mode of your choice then using lens correction tool to see how much (as a percentage or fraction) it take to make one look like the other.

If I do find the YouTUbe video with the review that gives the hardcore numbers, I'll post it here.   I saw it weeks ago while I was waiting for my Action4 to arrive in the mail.

Anonymous1 Posted at 11-4 14:13
What I understand is that just like GoPro, the camera uses the full sensor at all times (once not using De-warp).   What really changes is the fish-eyed look.

GoPro does ~10% crop in each increment of stabilization you enable.   I feel DJI does 10% crop first, then an additional 5% for Rocksteady+

That is very helpful, would love to see this video if you come across it again

lewlewland Posted at 11-4 13:37
I'm not encountering any issues necessarily. I'm just trying to find the widest angles in each aspect ratio and stabilization modes

Thank you for your clarification, lewlewland. We apologize as we don't have that information. Thank you for your kind understanding.