May 9th, 2010, 12:38 AM | #1 |
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1st Day with Blackbird!
Got my BBird yesterday (longest day of my life waiting for UPS who didn't deliver it til 6:30pm signature required!)
Spent time playing around with it and this morning got serious did the setup as per instructions. For the record, T2i with battery grip/2 batteries, Tokina 11-16 with protector glass and circular polarizer, no hood, Manfrotto 577 QR plate. This being my first foray into stabilizers, it went better than expected. Setting the balance was not terrible and the only thing I'm seeing is a tendency to lose horizon. Does this mean I don't have enough weight on the bottom? I am using the short bar with 2 large weights on each side.The bar height is at 6. My drop time is about 2 sec. I weighed the camera at about 3.5lbs including QR (not the whole plate just the camera part) As everyone else getting into this area, I want it NOW! But understand this is gonna take a while before it really starts to happen. I'll post some footage soon and get everyone to rip it apart. One last question, I was filming my kids running around and found it best to put a little downward tilt when balancing it so I could keep them in frame. Is this normal?
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May 9th, 2010, 04:58 AM | #2 |
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Hi Robert, looks like there are quite a few of us new guys! Anyway, yes I'm finding that if your tilt the camera slightly down it's more stable. When I have it really close to the tipping point but not quite it has a tendency to pan by itself unless I add more weight.
I see that you also have that lean going on when you turn. I think it's either a trick of the hand or the weights. |
May 9th, 2010, 09:22 AM | #3 |
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Yeah..the lean during turn is gonna take some practice. I'm determined to nail this though! Another thought came up after I shut down last night...
Is the battery grip possibly making the rig CG to high? Should the gimbal be adjusted to compensate?
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May 9th, 2010, 01:09 PM | #4 |
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I haven't tried messing with the gimbal height itself, I just have it tightened up showing about 3 rows of teeth. If you look at CarPa's video, he has a QR plate, a rail, then another QR plate on top of that.. It looks like he's using about 4 weights on each side too.
My current observation about the lean, if you raise the bar there's less of it. But sometimes I get it even with the bar raised. Maybe it's in the wrist movement that neither of us has noticed yet? As long as you have the subject in front of you the viewer will probably not notice the leaning or bobbing so much. I only notice it now because I'm looking for it. |
May 9th, 2010, 04:41 PM | #5 |
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Good points! And good vid example too. This is going to make watching TV and movies even worse as now there's a whole new category of shots to put under the microscope. But that's how we get better at what we do!
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May 9th, 2010, 09:57 PM | #6 |
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Some comments and suggestions
Interesting discussion here. I would like to provide some information and suggestions. I’ll apologize right now for such a long reply, but I just can’t help it.
Aside from paying attention to where you are going so as not to trip or bump into something, and getting framing the way you want it, the hardest thing about getting good handheld stabilizer shots is minimizing any unwanted roll or tilt motions sometimes called penduluming. For all handheld gimbal stabilizers, one hand supports the rig and the other hand must guide the camera in the pan, tilt and roll directions. But more than just pointing the camera in the right direction, the control hand must provide adjustments for any unwanted roll or tilt motions like penduluming. For the Blackbird usually just the thumb and index finger placed on the upper control ring above the gimbal provide the guiding and penduluming correction (the gimbal locking nut just below the stage can also be used). For most shots where tilting the camera up or down is not needed, the thumb and finger should not be tightly griping the control ring because that will tend to result in over-controlling. The touch should be very light. In fact for shots where tilt isn’t needed I suggest trying a kind of non-continuous contact of the thumb and index finger on the control ring, just a rapid and gentle tapping sort of contact to make fine adjustments. Balancing the camera tilted down or up will not improve stability. But for any continuous shots with tilt it is best to balance for the tilt angle. This will reduce the strain on your controlling fingers and will also reduce any tendency to have unwanted panning which is easy to get when you do forced tilt shots. Keeping the horizon is probably the most frustrating challenge for beginners, and for sure many just give up and put the stabilizer in the closet. It takes skill, and lots of practice to get acceptable shots, but it does become more automatic after time. It’s not that you won’t always need to concentrate, you will. But it will become easier. To help you appreciate this, let me mention that I usually support with my right hand and control with my left hand fingers. I have often thought I should practice switching hands, if only to allow giving my right hand and arm a rest when flying with a heavy camera. But of course I never get shots as good when I reverse hands because with lots of experience/training, my eye-brain-hand coordination has become more automatic with my normal left hand control mode. In other words when I switch hands I become more like the beginner I once was. In fact this is now my academic (cop out) reason for not really working on the hand switch….so that I can try to remember what it is like as a beginner. With regard to stabilizer rig performance there are two essential things you should understand. First for any camera and accessory weights the vertical balance or drop time is most important to minimize penduluming. Two seconds is a good time for any weight rig. Below about 1 second penduluming can be pretty bad, and so harder to control (won’t go into the why’s of that in this thread). Above 3 seconds and the rig will not balance very easily horizontally and will tend to drift. I’ll temporarily leave the subject of drop time to talk about rig stability The second thing to know is that a rig’s real STABILITY is largely determined by its moments of inertia in the three axes of rotation which are pan, tilt and roll. With a higher moment of inertia in any axis there is more resistance to rotation in the axis for a given force (actually a torque) acting on it. This may getting too techy talk for many, but perhaps you can believe that if you had a very small and light stabilizer that you could gently touch it to cause it to rock, but the same gentle touch on a larger and heavier stabilizer would produce much less rocking. The only other thing you need to understand is moment of inertia depends not just on weight, but also the square of the distance from the weight to the axis of rotation. In short pure weight isn’t everything, it’s where you put it. AND, you should understand that a rig with very high moments of inertia can pendulum just as easily as a small rig. BUT, it is less susceptible to wind or just the aerodynamic drag on the camera body etc. when it is moving, and a much higher and less delicate, so generally easier to master touch is required to stop or prevent penduluming. That’s precisely why Carlos Padilla used rails and quick releases to add weight and raise up the camera on his rig which also required adding more counterweights, all of which significantly increased the rig’s moments of inertia and feel. Of course the down side is the rig gets very heavy. Now back to drop times and an attempt to tie together everything above, and hopefully explain the answers to some questions like should the gimbal be high or low or does it matter, what about adding more weights, etc. Always remember the drop time mantra….go for about 2 seconds, a little more or less is operator preference, but generally less than 1 second or more than 3 seconds won’t work well for most people. On the Blackbird you can adjust drop time by doing a combination of three things: 1) changing counterweights, 2) raising or lowering the T-bar, 3) adjusting the gimbal up or down a little. And here is the guiding principle… Getting the T-bar set low will result in the maximum moments of inertial in the tilt and roll axes. So for whatever rig you have while balancing to achieve the 2 second or so drop time you should use counterweights and adjust the gimbal postion (if necessary) to get the T-bar low….period, end of story. The gimbal position itself will not affect stability. And balancing to tilt the camera will not help stability in itself, but as mentioned will make it easier to control. But it’s not the end of the world if the T-bar is raised up. You may want to balance with it raised up for low shots where you want to get as close to the ground as possible. Having explained that penduluming can be reduced by getting the drop time slow enough, the other thing to remember is that the forces that cause penduluming in the first place are accelerations (sudden starts) and decelerations (sudden stops) and moving in an arc. So you want to minimize all of those as you move around. Try to be stealthy. This is also one of the times your support hand comes into play in stabilizer performance by minimizing sudden starts and stops. Imagine it is like a spring that dampens your body movements. Finally don’t forget about the gimbal friction adjustment we call Smoothtouch. Here’s a quick guide. Hold the Blackbird by its arm with one hand and lift the free swinging handle to about a 45 degree angle and then let it drop. With no gimbal friction it will pendulum (sorry, hate to use the same term as used for the whole rig) about 6 times or so before coming more or less to rest. A pendulum here is defined as a full swing one way and back. Now start adding some gimbal friction with the adjuster until the handle only pendulums perhaps 2 or 3 times. Then try some shots and you should see a reduction in unwanted rig pendulum motion. Experiment with more or less friction. There are some downsides to adding gimbal friction which are a little more (unwanted) coupling between the rig and the handle, less sensitivity to making horizontal balance adjustments (may seem a little sticky), and for handle angles noticeably off vertical there will be an increase in pan friction. But I suggest you try it. Hope this helps. Rich Greb Camera Motion Research |
May 9th, 2010, 10:44 PM | #7 |
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Thanks Rich, that helps!
Just want to clarify something about Carlos' setup. Did he add the 2 QR and Rails primarily to add the weight? Or was raising the camera, which I think also changes the rig's center of gravity, also necessary? I ask because of this video where a blackbird was used on a moving boat. |
May 10th, 2010, 05:34 AM | #8 |
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MIke, good question and points out something I didn’t talk about. If you didn’t change anything else both adding weight and moving the camera higher would certainly change the CG of the rig. But don’t be concerned about whether it was added weight or added distance of the camera from the gimbal. Because Carlos wasn’t primarily changing the CG of the rig! More counterweights had to be added and the CG of the rig was probably not changed much.
Adjusting the drop time is what determines where the CG of the rig is. Carlos’ rig may have been just as susceptible to acceleration/deceleration caused penduluming as a lighter rig. But the rig moments of inertia were much higher than otherwise, and so it would be less susceptible to wind and would also as I mentioned require less delicate control with the controlling fingers. A heavier rig could also allow setting a somewhat longer drop time that does reduce penduluming , but still balance horizontally OK and not drift as much as a lighter rig with the same drop time. So in that case the CG might be moved a little closer to the gimbal, but I think mainly the moments of inertia were increased. For shots from a moving boat I believe that shielding the rig from the wind is more effective than increasing moments of inertia of the rig. Rich |
May 10th, 2010, 09:04 AM | #9 |
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Rich....YOU ROCK!
Thanks so much for the detailed post. (you should include that with your instructions!) Day two, I switched to the longer bar which seemed to help a lot and using my "guide hand" also was a major improvement. I think I'm gonna like this!
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May 10th, 2010, 10:10 AM | #10 |
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Did he add the 2 QR and Rails primarily to add the weight?
Yes, I add the bars and QR to add more weight to counteract the wind, but anyway I want to say that I like the feeling you have with more weight. Rich explain better than me WHY (sorry my english isn't good enough to explain technical issues) Yesterday I did a quick test with the sony ex1 to see how the BB can handle this range of cameras. I'll post the video. Another thing I want to comment. In the video above I use a 35mm lens in a full frame camera. I don't know you guys but I see that below this (for example with a 24mm) is very difficult to avoid the horizont problem and also can do your steps visibles. 24mm in an aps-c sensor would be good |
May 10th, 2010, 11:54 AM | #11 |
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Any recommendations on a vest for the BB?
I've received mine and love it, but had surgery on my supporting elbow last year and need a vest for longer takes. Thanks |
May 10th, 2010, 12:11 PM | #12 |
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No question, the Tiffen Merlin arm and vest. The Blackbird handle will fit right over the stock angled post at the end of the arm. But we have a modified post that works better. Send us an email for details.
Rich Greb Camera Motion Research |
May 10th, 2010, 12:12 PM | #13 |
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I had a glidecam x-10 and it works but didn't like it too much.I wanted to buy the merlin/pilot arm & west but finally I didn't. Rich send me a post to join the BB with the steadicam arm. I think it can a very good combo
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May 10th, 2010, 06:07 PM | #14 | |
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Quote:
I have the steadicam merlin with Arm and Vest and love it for it's lightness. Then wanted more stability in the wind, so I got the hybrid attachment to put a glidecam HD4000 on the arm and vest... worked great, except the glidecam was too heavy for me. Went back to the merlin, but I like the BB's friction adjustment technology, so thinking of attaching that the the Steadicam Arm + vest. Thanks, David |
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May 10th, 2010, 06:33 PM | #15 |
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friend of mine has a Pilot...gonna try his vest! (maybe I won't give it back!) HaHa!
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