zukenj

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Preferred Flights modes for aerial photography
« on: May 12, 2017, 02:05:51 pm »
What is your preferred flight mode for aerial photography?

FS-TH9X RC
F450 Clone
Revolution FC
EMAX 2213 935 KV
HK 30A ESC UBEC running BLHeli 14.4
10x4.5 Propellers
DJI Naza clone Ublox M8N GPS

Re: Preferred Flights modes for aerial photography
« Reply #1 on: May 12, 2017, 09:20:39 pm »
(Caveats: The (A)erial (P)hotography that I do is more to celebrate the flight than to frame the perfect scenery video.  These opinions are mainly for multicopter vehicles.  Fixed wing vehicles probably need different settings.  There are several different preferences: what produces the best video quality of a picturesque scene, what produces the best video quality of stunt flight, and what the pilot likes to fly when shooting video.  :)  Stunt flight needs a fixed camera mount and won't be considered further.)

One of my AP aircraft has an inexpensive stabilized 2D external gimbal and the rest have fixed camera mounts.  If you have a good "external" gimbal (not the gimbal signals coming from the FC) that uses it's own sensor, it doesn't matter what mode you fly in from the standpoint of picturesque scene quality, since it removes all jitter and flight motions.  Unfortunately, using the "FC provided gimbal signals" does not remove the small INS13 jitter caused by the compass.  So, use an external gimbal to get the best video in any flight mode.  It might be possible to tune this INS13 jitter out by changing *PathFollowerSettings / EKFConfiguration at the expense of long flight stability and quick reaction, but that is a large topic that belongs in an advanced discussion.

To recap if you don't use an external gimbal:  INS13 causes a small amount of jitter, even in the non-GPS Attitude mode.  Even if that didn't happen, all GPS flight modes add a small amount of correction for wind and GPS wanderings.  Default LP settings tend to choose quick reaction and accurate GPS positioning over smoothness.

All of my LP quads have a GPS and use INS13.  Some of them have a camera of some kind.  Only one has an external gimbal.  So, even though a lot of what I fly doesn't have any kind of gimbal and uses INS13, I don't find it a problem and I still enjoy my videos.  In my opinion, it's if you want commercial quality video that you need to worry about INS13 / GPS jitter.

This INS13 jitter (which is only important if you use INS13, you don't use an external gimbal, and you need really high quality video) comes from using the full 3D compass as part of the attitude estimation.  This means that using Basic "attitude estimation algorithm" will hold the camera very steady in Attitude mode, but INS13 (GPS Outdoor) will have a small amount of jitter in that very same same Attitude mode.  I recall hearing that the next release has a solution that may allow GPS flight without this INS13 jitter.  If you build your own software, this might already be available in "next".  I don't know much more about it.  This might correct the small jitter you get without a gimbal in INS13 Attitude mode, but the jitter from using any mode that requires GPS (e.g. VelocityRoam) will always be there unless you change your *PathFollowerSettings / EKFConfiguration to forsake quick reaction and exact position hold in favor of smoothness (this seems to be what DJI Naza does).

I like VelocityRoam (which needs GPS and INS13) because it stays where you put it, even in the wind; it's like PositionHold but you can drive it around.  Of course, if you don't use an external gimbal, any flight mode that uses the GPS will have small constant corrective motions that will be noticeable.  These can be removed if you detune the the *PathFollowerSettings / EKFConfiguration to forsake quick reaction (e.g. to gusty wind) and exact position hold in favor of smoothness (this seems to be what DJI Naza does).  Once you do that, then maybe the new INSxx modes in next with Attitude mode with GPS Assist would probably give you the smoothest flight with good performance, but that is a lot of marginally useful advanced tuning work if you don't need real commercial quality video.  I certainly won't bother to do it.

There are some very interesting GPS flight modes that I haven't even tried.  In particular, a quick look at the code seems to say that with CourseLock mode you can hold a course by holding a fixed position on one stick or even just a lot of forward pitch trim (or using transmitter mixing to mix a knob into the pitch to allow the knob to set a constant forward speed) and while it is flying that course you can use the yaw stick to follow a point of interest as you fly by.  This mode effectively turns a 2D gimbal into a 3D gimbal but it should work fine without a gimbal.


On related notes:

Especially for higher def video, you can use post processing to remove jitter and excess motion.

Easytune and AutoTune both have settings to allow you to tune your PIDs for photographer (smoother flight) or FPV racer (quicker reaction).

If you are mainly a photography guy and this is just to get a picture taking platform in the air, you can buy a complete DJI Naza FC / GPS / BEC / LED for $69 shipped on eBay.  I bought one (OK, more than one at that price :) ) to play with and see what the other side is doing.  The authentic DJI Naza GPS (it may be better to get a clone if you intend to use it with LP) it comes with costs about $39 by itself.
http://www.ebay.com/itm/DJI-Naza-M-Lite-GPS-Compass-Multi-Rotor-Flight-Control-Stabilization-System-/191388772291

Many people fly FPV, and their FPV camera is mounted at an angle.  Be aware that 1609 has a feature that allows you to have your flight commands automatically translated into the FPV camera angle so that for instance a roll flip would be centered in the center of the FPV camera.
« Last Edit: May 13, 2017, 01:09:29 am by TheOtherCliff »

ernstock

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Re: Preferred Flights modes for aerial photography
« Reply #2 on: May 13, 2017, 09:39:42 pm »
Many thanks for this , Cliff.
Am slowly getting an aerial platform together , and keenly following your advice.
May I ask : can these position assisted flight modes be in either attitude or rate ?
I sort of feel that such craft 'should' be flown in attitude , but am more comfortable in rate.

 (Thanks for the heads up re the fpv cam angle feature - have researched it a bit and am keen to try it on my acro+ 180 size 'racer' - I wonder what effect it'll have on flight in general , but rolls without the need for pitch adjustments is intriguing. )

Re: Preferred Flights modes for aerial photography
« Reply #3 on: May 14, 2017, 04:53:47 am »
Quote
May I ask : can these position assisted flight modes be in either attitude or rate ?

I honestly don't know.  You can probably use GPS Assist with Rate Mode, but I have never tried it.  Easy to see if it arms.  GPS Assist basically just means it switches to Position Hold when you release the sticks.

ernstock

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Re: Preferred Flights modes for aerial photography
« Reply #4 on: May 14, 2017, 10:05:12 pm »
Quote
May I ask : can these position assisted flight modes be in either attitude or rate ?

I honestly don't know.  You can probably use GPS Assist with Rate Mode, but I have never tried it.  Easy to see if it arms.  GPS Assist basically just means it switches to Position Hold when you release the sticks.
Thanks.

I tried fpv camera angle setting today. Very pleasing to have a flight mode for high up horizon-based rolls , but 'normal ' / acro+ setting for proximity flying is handy to switch back to. 
I suppose the fpv cam setting is like putting the same degrees setting on board attitude - pitch.

zukenj

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Re: Preferred Flights modes for aerial photography
« Reply #5 on: May 16, 2017, 03:55:32 pm »
TheOtherCliff,

Thanks for you reply, I do have a 2D external gimbal, and that is why I ask.

You mentione that you like and use VelocityRoam, I will have to ply wiht it a little longer. Have you try HomeLeash?

Thanks
FS-TH9X RC
F450 Clone
Revolution FC
EMAX 2213 935 KV
HK 30A ESC UBEC running BLHeli 14.4
10x4.5 Propellers
DJI Naza clone Ublox M8N GPS

Re: Preferred Flights modes for aerial photography
« Reply #6 on: May 16, 2017, 07:43:37 pm »
I honestly haven't.  I either fly FPV and so VelocityRoam is best for me, or I fly LOS which still doesn't need HomeLeash .

To me, HomeLeash is a safety mode that you would switch to if it got too far away when flying LOS.  I find that center stick VelocityRoam does a good position hold to give me time to figure it out if I am too far away.

zukenj

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Re: Preferred Flights modes for aerial photography
« Reply #7 on: May 17, 2017, 08:54:06 pm »
Thank. Make sense.

Appreciated your help.
FS-TH9X RC
F450 Clone
Revolution FC
EMAX 2213 935 KV
HK 30A ESC UBEC running BLHeli 14.4
10x4.5 Propellers
DJI Naza clone Ublox M8N GPS

zukenj

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Preferred Flights modes for aerial photography
« Reply #8 on: May 23, 2017, 01:54:24 am »
Thank. Make sense.

Appreciated your help.

Today I did my first FPV..... Did not crash. I use homeleash, and it was ok. A little sluggish, but I know why. On homeleash, it try to label and that course the quad to rock back and fords and it was a estrange feeling .

I have to try velocityroam like theOtherCliff mentioned


Sent from my iPad using Tapatalk
« Last Edit: May 23, 2017, 01:57:50 am by zukenj »
FS-TH9X RC
F450 Clone
Revolution FC
EMAX 2213 935 KV
HK 30A ESC UBEC running BLHeli 14.4
10x4.5 Propellers
DJI Naza clone Ublox M8N GPS

Re: Preferred Flights modes for aerial photography
« Reply #9 on: May 23, 2017, 04:47:21 am »
First FPV.  Did you make a video?   8)

If you have DJI/Naza GPS, there are east-west oscillations (usually with authentic DJI/Naza, but some users report the issue with the DJI/Naza clone also) and it does not matter which way you are pointed.
https://forum.librepilot.org/index.php?topic=3012.msg21154#msg21154

zukenj

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Re: Preferred Flights modes for aerial photography
« Reply #10 on: May 23, 2017, 01:39:59 pm »
First FPV.  Did you make a video?   8)

If you have DJI/Naza GPS, there are east-west oscillations (usually with authentic DJI/Naza, but some users report the issue with the DJI/Naza clone also) and it does not matter which way you are pointed.
https://forum.librepilot.org/index.php?topic=3012.msg21154#msg21154
TheOtherCliff,

No I did not. I didn't know how it will be, and my setting will not allow recording from the FPV, for now. I read that post last week, and​ I was about to ask, if mine does not have the issue, will it be ok to flash that firmware?
 
From outside looks pretty steady in PH, but in the FPV you can see the rocking.

I will flash the firmware you post and give it a try.

Sent from my SM-N900P using Tapatalk

FS-TH9X RC
F450 Clone
Revolution FC
EMAX 2213 935 KV
HK 30A ESC UBEC running BLHeli 14.4
10x4.5 Propellers
DJI Naza clone Ublox M8N GPS

Re: Preferred Flights modes for aerial photography
« Reply #11 on: May 23, 2017, 09:00:21 pm »
The only thing that firmware changes is that it reduces oscillation in GPS modes if you have a DJI/Naza GPS.

Do you have a DJI/Naza GPS?

It is completely compatible with 16.09 so you don't need to change settings after flashing the firmware.

zukenj

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Re: Preferred Flights modes for aerial photography
« Reply #12 on: May 23, 2017, 10:05:20 pm »
The only thing that firmware changes is that it reduces oscillation in GPS modes if you have a DJI/Naza GPS.

Do you have a DJI/Naza GPS?

It is completely compatible with 16.09 so you don't need to change settings after flashing the firmware.
Yes. Is a clone, but DJI Naza

Sent from my SM-N900P using Tapatalk

FS-TH9X RC
F450 Clone
Revolution FC
EMAX 2213 935 KV
HK 30A ESC UBEC running BLHeli 14.4
10x4.5 Propellers
DJI Naza clone Ublox M8N GPS

Re: Preferred Flights modes for aerial photography
« Reply #13 on: May 23, 2017, 11:52:46 pm »
If the oscillation is repeatable, then try that firmware and see if it helps.

The request for video was not to see the oscillation, but to see your first FPV flight.  :)  For the really adventurous ones, It's like watching a good movie that you have seen before.

zukenj

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Re: Preferred Flights modes for aerial photography
« Reply #14 on: May 24, 2017, 01:42:34 pm »
If the oscillation is repeatable, then try that firmware and see if it helps.

The request for video was not to see the oscillation, but to see your first FPV flight.  :)  For the really adventurous ones, It's like watching a good movie that you have seen before.
About the first flight, let me tell you I love it, but it was baddddd.

I have to get custom to the view angle of the camera, then I had some sun in the camera, but did not crash (hard) .

 I flew until it was out of battery. I did initial approach, and try to move the quad forward and putting some yaw in a constant velocity, so I can get a filling on altitude and distance from objects​.

Suggestions are always welcome.

Sent from my SM-N900P using Tapatalk
FS-TH9X RC
F450 Clone
Revolution FC
EMAX 2213 935 KV
HK 30A ESC UBEC running BLHeli 14.4
10x4.5 Propellers
DJI Naza clone Ublox M8N GPS