Glidecam 2000 drop time

[Boyd Ostroff]

Have been experimenting with my new Glidecam 2000 and PDX-10; lots to learn! After refining the balance some more I'm using 4 of the weights and the shaft extends about 1.5" from the clamp. It seems to balance as it should, and the drop time is about 2 seconds, as per the manual.

However I still seem to get excessive side to side sway. I tried adding two more weights and shortening the shaft all the way. This appears smoother, however the drop time is only about 1 second, maybe less. The manual doesn't really explain why it's desirable to have a longer drop time... any insights?

I'm wondering if the basic problem is that the PDX-10 is such a light camcorder to start with (~2 lbs)? Obviously this makes it much easier to hold on the Glidecam, but do I need to actually add some weight to the camera itself to make it balance and still have the recommended drop time?

FWIW, I'm using a .45x wide angle adaptor and the large lens hood as well.

[Charles Papert]

Boyd:

The reason for the 2-3 second drop time is that it is a generally accepted compromise between "too bottom heavy" and "not bottom heavy enough". In the first instance, such as you have it now, coming to a fast stop or moving quickly to the side will cause a pendulum effect because of the difference in mass above and below the gimbal. The ONLY way to eliminate this is to make it neutral, i.e. infinite drop time, but you get no "feedback" from the rig as to where level is, i.e. you are constantly having to "make" the rig find level. That's the problem with "not bottom heavy enough".

Another reason not to work with a fast drop time is that takes much more effort to hold a severe tilt (45 degrees or more up or down). Having to use a heavy grip on the post means compromising the delicacy of the operating and the results.

As far as the side-to-side sway, you should balance the rig back to a 2.5 second drop time and try the test I described to Devin and Spence in this thread. If, without your operating hand on the post and a slow, steady forward or backwards walk you are still seeing a lot of rocking in side-to-side, there is a problem with the gimbal, especially the roll bearings (this is the two bearings at either side of the gimbal, where the fork attaches to the pan section around the post). I would contact the factory if this is the case.

Be aware that even if the rig is perfectly fine, having a lot of roll (side-to-side movement) in your operation is not at all unusual for a "newbie". It's all about the fingerwork on the post.

[Boyd Ostroff]

Thanks a lot Charles! Ah, this is just as I feared, there isn't any substitute for practice and hard work... ;-)

[Timothy Eno]

Boyd, I am using about the same setup. 5 weights and approx. 1.5 inch exstension. That is with Large hood, external mike, and Qm71 battery and it works pretty well for me. It took some time to get my fingers with the program and then my results improved . As I have learned it takes a lot of practice to get the results you want.

[Boyd Ostroff]

Tim, thanks for sharing your setup. This actually matches mine pretty well, I also have the large battery and lens hood. Where we differ is that I have a WA lens (which is pretty small and light) and am NOT using audio so no mike or XLR box. That would pretty much account for the extra weight you use.

BTW, it's funny how they talk about "weight disks".... they're just large washers! It's a nice setup though, and I'm sure my work will improve with a little more PRACTICE! :-)

[Boyd Ostroff]

Hey, I just discovered a nifty trick to refine the front to back balance using the PDX-10. Instead of messing around with the thumbscrews and plate, try sliding the PDX-10's moveable viewfinder back and forth! It weighs just enough to tip the rig one way or the other.

[Charles Papert]

Great tip, Boyd, and that reminds me to remind everyone out there using stabilizers that you must be fanatical about tying down anything loose on the camera--no flopping cables, lens caps on leashes, viewfinder mounts etc.