I'm relatively new to this aerial stuff (5 months now). I am getting some nice stuff, but I'm finding I have to do post processing because my cameras have too much shake. I'm flying a CS8 with 3 axis radian gimbal. Gains set in the mid 70's to 80's. I'll be the first to say I have never achieved "perfect" balance of the camera (got close but not perfect). I changed supension to 4 blue and 3 red rings which stiffened it up and it seems better... but is this video the best I can expect? I must be able to get closer. Is it a given that to get a glass smooth image you have to post process. This flight was in little to no wind. Little to no pilot inputs, and gimbal is performing smoothly. I want to use as little post process as possible because software seems to struggle with the z axis when you are close to treetops etc... but lateral movements come out fine... but the sharpness is slightly reduced. This video has 12 seconds of final imagery, then a repeat with a split screen so you can see raw vs. post, then the same repeats with just raw. I left the motor noise on so you can hear the motors. Also, this flight has plastic props, I'm down one wood xoar so I had to go plastic (ick). You can be kind, cruel, just give it to me straight! Thanks for any suggestions or tips.
What camera are you using? Balancing the camera is super important, and if you get it right, it can make all the difference. The servo/belt combo on the Freefly gimbals is very sensitive to balance. You may also want to experiment with the Mikrokopter flight control board gyro PIDs and other numbers, as you may be seeing some oscillation in the frame itself due to the copter overcorrecting. I think I'm having the same problem at the moment. Thiago Kraus has done some videos that show how some of these settings can affect the stability of the Cinestar. I went through all that at one point and got it very smooth on mine, but when I upgraded to the newer altitude sensor, my settings no longer worked well. So I have to do it again.
Thanks.. This is the 5DMkII with a 24 - 105 lens. I will check out those videos. Is there anywhere to find a good instructional video on balancing. The freefly one picks up with the gimbal and everything in place. Is it best to start with the roll axis? And how the heck to you manage all the hex heads that if they are loose enough to move the pole, it falls apart, or if its too tight and holds in place you can't move it enough. One question I have... my roll servo is always making a bit of noise even when sitting still with the camera on it. Should it be silent? Is that the sign of a well balanced gimbal?
That is a pretty heavy camera/lens combination. It is a dance. Best to have the copter suspended at your eye level, and work all the screws to the point where you can nudge things a little, but they'll hold. It's also important to remove the belts from the pulleys. And getting the height of the camera in the saddle is also hard if you don't have the newer Dual Adjustable Tilt Bars. http://www.quadrocopter.com/Dual-Adjustable-Tilt-Bar_p_848.html
Hey Steven - I am getting similar shake on mine and plan on going thru the PIDs this weekend and see if I can adjust anything. My Radian gains however are way lower than yours. I might have to take a look at that too. What software do you use for post stabilization? I see it does a pretty good job at it.
After Effects with the warp stabilzer. Let me know if you get any numbers on the PID's. I appreciate any suggestions.
Switching to a Canon EF lens with IS on it helped take almost all the little shake out. Steve's right the lens you are using is quite heavy and might compound the issue. Here's before I switched to the IS lens Here's after
Thanks for the sample. I was using IS on the 24 - 105, I'm working on sourcing a 24mm prime IS for this weeks shoot... and following the tons of advice on the other threads. You really have to get up the energy to tackle all the variables to get the fine tuning in. Looking forward to the challenge.
Steven Perhaps try a all blue o-ring setup. I am not seeing any high frequency vibrations hitting your camera in your videos just a bit of bounce. May help to stiffen up your interface just a bit. There is a sweet spot. Payload and temp dependent. I have found for med to heavy payloads all blue o-rings work well in most cases. I know it's tough but become a master at camera balance. It goes a long way to achieve perfect balance. cheers Mike
Steven, For balancing its best to start with tilt, then roll, then pan. If you think about it the logic is that tilt affects roll and both tilt and roll affect pan. Any other order and you'll end up doing an axis or two more than once. Remember, always balance without belts and radians unplugged. You want the least amount of things affecting the free motion of the gimbal. So excuse me for being long winded here.. I just finished and realized you probably know all this but maybe it will help others.. For tilt, it is important to have the vertical side bars parallel to the camera body as viewed from the side. This also helps with roll balance.. ill explain in a minute. Tilt also has two adjustments and most times you'll have to adjust each a few times to get it perfect. I get the forward to aft balance on the camera plate first and then move to the vertical adjustment with the side rails. Depending on how far off your vertical balance was you may have to go back and fine tune each of those a second time as one affects the other. To test the vertical balance, point the lens vertically towards the ground and release. If it swings forward (camera upright) your bottom heavy and the camera needs to move up. Of course swinging back (camera upside down facing backwards) your top heavy. No movement? Your ready for roll. There are two places you can make roll adjustments. You can loosen the bolts that hold the roll tube in place and slide it left or right or move the camera tray left or right. I prefer the second only because when you loosen that roll tube all the camera weight cantilevered that far forward makes it impossible to maintain your roll neutrality balance.. (thats what ill call it, i'm not good with words but I can balance in minutes!) If the camera weight is too low on the roll axis when you release, it will center with the roll tube horizontal and the camera in a nice level position. Great you may say but thats not balanced, just bottom heavy. If the weight is too high it will roll off the top end and the roll tube will be hard over in one direction or the other. Roll neutrality balance should never change once you get the gimbal setup. No matter what camera or lens combination, the position of the tilt axis will always be in line with the roll axis. Therefore by not adjusting that back roll tube your saving a step... every time. If I find a roll adjustment is required because of a camera change, I know it will only be a left to right motion and not a neutrality issue because I've set that. Now loosening the clamp that holds the camera plate will also leave you with two adjustments. You have left to right but also the camera will want to rotate on that tube. This is where having the camera parallel to the tilt bars helps. Adjust your left to right movement but be sure that when you tighten it back down the camera is still aligned parallel to the tilt bars. Now you know you didn't accidentally adjust tilt while messing with roll. Everything neutral in tilt and roll? Move on to pan. Pan is probably the hardest to visualize. The clamp that holds the vertical tube to the top horizontal pan tube is the only adjustment. Issue is that it affects two aspects of pan balance. There is front to back movement on that horizontal tube but also rotational movement there that affects the "neutrality" of pan. Its also a case where one affects the other so you may have to go from one to the other a few times to get it perfect. I start by having the clamp tightened with the vertical tube completely vertical and then check the front to aft balance. To do this I hold the mount at a slight angle with the pan axis perpendicular to that angle. This is all the same for balancing a 3 axis, MoVI, or MR but to better visualize this ill use the multirotor setup as an example. With the gimbal attached to the copter and the copter hanging from a point, lift the back of the copter to give it a slight nose down angle. Position the pan axis to face in a left or right direction (90 degrees off of the lift motion) hold and release. If the back of the gimbal goes low, you have the clamp too far aft on the horizontal pan boom. If the back of the gimbal moves high, its too far forward. Once you have this motion fairly stable you can check the other adjustment. With the pan axis now facing in line with the copter, release. If it rotates one way or the other, the rotation of the vertical boom needs to be adjusted. Do this at that same clamp on the horizontal pan boom but be careful not to slide fore or aft. When your done you may have that vertical boom rotated off to one side or the other. It wont be much at all but just a little off and the balance will be way off. The goal is to be able to position the gimbal in any position and it stay. My experience with the MoVI setups is that they are actually easier to balance and more tolerant of slightly off balance. And by slight I mean it will handle a lot but you will notice it in footage if you do a terrible job. The 3 axis radian setup is more critical because you are dealing with the limits of the servo and belt system. Perfect balance is one less thing they have to fight. Again sorry about the long post but I feel someone with benefit from my experience balancing with all these setups. Most have been in fairly high stress- low time situations. With a little practice it becomes second nature and quite a quick and easy process. Thanks for your time!