Camera Repaired -- Now Heavier, and Glidecam Problems!
 

Ok, so my internal speaker been fixed on my Canon XH-A1, it's been cleaned, and the firmware updated, so I brought it home, and strapped it onto my Glidecam 4000 Pro. I was expecting it to need minor rebalancing, but I wasn't expecting the camera to be heavier than it was before!

Prior to having the camera repaired, I used a total of 8 weights on the base plate (4 each on the front and back), and I had a drop-time of 3 seconds. The dynamic balance was pretty darned good too. Now, I have to have 10 weights on the base plate just to stop it turning upside down! With the Central Post almost all the way collapsed, my drop time is closer to 2 seconds. The dynamic balance is nowhere near what it was, and the camera wants to pan as I move.

I've spent nearly 4 hours trying to get it right... longer than I did when I first got the Glidecam.

Any suggestions? I was hoping to use my rig tonight at a charity event, but I may just go handheld instead!

Hi Julian..........
 

Bigger battery, perhaps?

Something mounted up top that wasn't there before?

Just shots in the dark.


CS

Chris,

I wish that were the case. I gave them the camera with nothing in it, nothing attached (not even a front element UV filter), and got it back the same way. I put the exact same accessories back on the camera (same battery, same filter, same SD card) and got the results I mentioned.

After writing the first message in this post, I decided to remove the extra weights (so I could regain some of my drop time), pull the central post out a bit further, and move the weights around a bit on the base plate. It's back in static balance again, but I'm flummoxed as to why the camera was *so* different. Nothing moved on the Glidecam during the day the camera was at the repair facility, and I've successfully removed and replaced the camera from the Glidecam in the past, without experiencing these balance problems.

I had my new setup balanced perfectly, then the following day my bogen 577 quick release adapter showed up. I marked the cameras location, added the adapter, and the added weight of the adapter, as well as raising the camera an inch threw everything off. I had to start all over with balancing. I figure its good practice....

I went through the same issue -- got a QR plate for the Glidecam so had to go through the entire process again. It was much quicker the 2nd time around. But this is baffling! It's the same camera with EXACTLY the same stuff attached to it or inserted inside it! Even down to the same tape! I've marked the position of the LCD screen as well, so that's not an issue. The camera is just heavier! Like I said earlier, I've got it static balanced again with the original weights after moving the weights on the base plate around, but it's not anywhere near as nicely dynamically balanced. After shooting this evening, I'll try some of Charles' suggestions to get the dynamic balance dialed in.

Here's the test I did earlier. It should be a bit better now.

http://vimeo.com/937588

Julian, you will find that after few months of rebalancing it many times (when you add WA, mic, then take it out and put it again) you will do it in no time.
I just had an emergency, where I couldn't use my A1 on GL and had to rebalance it for HV20. It took me 5 min at the most.
So keep practicing :)

I agree, practice makes perfect. But don't you think it strange that the camera would be completely top heavy... so much so, that it caused the Glidecam to flip over upside down?

I don't have a clue. It's strange.

I bet they left a hammer or something inside your camera by mistake...

Hahaha! Who do you think they are, King-Harbor Hospital? :-)

Out of curiosity, lol, did you check to see if the camera they gave you back had the same serial number? ;)

EDIT:

BTW, good to meet another Frost! Not a lot of us out there.

Hey brother! :-)

No, I didn't check the serial number... but I do recognize the dust! Ha! Yeah, it's my camera!

I used it this evening (eek, make that "last night") at the charity event and got some decent footage considering the run-and-gun nature of the shoot. Though the dynamic balance isn't perfect, the footage was way better than hand-held. Even the static stuff looked like it was on a tripod.

Pendulm-ing!
 

I bought a pair of small spirit levels, mounted them on the base plate of the Glidecam 4000 Pro, and rebalanced the rig while it was resting on its stand. I then picked it up, and watched as the rig moved off balance again and settled in a totally new attitude! Hmmm.

I made several small adjustments and got it so that it was balanced while holding it. I did the arc test, and measured the drop time at just under 3 seconds. I faced "north", and pointed the Glidecam "east" and walked forward, as if doing a tracking shot, and the Glidecam began to pendulum (the base plate stayed static as the camera moved with me).

In this case, my instinct tells me that there's too much weight on the base, hence it gets left behind when I move. But if I reduce the weight or shorten the center post, the camera will flip over!

Any suggestions?

what does it do when you spin it? does it spin flat?

I have a hard time spinning it without introducing wobble. That is, giving it a fair spin without user-induced unsteadiness. That said, if I spin it quickly, then use my free hand to control the center post so that I get it vertical again and at the same time slow it down a bit, it appears to spin flat -- even though I can feel through the handle that it's a bit lens-heavy. By holding the center post horizontal and allowing the rig to rotate in place I know that the camera is right-side heavy. I've been totally unable to correct that. When I do the arc drop test, the camera spins around "randomly", showing me it's not dynamically balanced.

I sent an email to Glidecam asking if I should give up on this 4000 Pro, or if anything can be done about it. When I hold my statically balanced rig in my hand, it'll slowly rotate to the right. If I rotate the handle by 180-degrees, it does not maintain its balance. To me this yells that the gimbal is not linear. There's also some play in the handle too. Add this to the fact that when I tighten the screws on the mid- and head plates, the COG changes (due to the plates distorting and/or moving under the different forces from each screw). This means I'm always chasing the balance. My rig may be front heavy in one test, then, when I move the head plate back and tighten the screws, it can be even more front heavy, or side heavy -- or who knows what -- because as the screws tightened, the plates moved slightly diagonally in relation to each other!

If the plates were secured in such a way that they could only move at exactly 90-degrees from each other, say, in a tongue and groove-type arrangement, that would surely help. But they're held aligned by screws which slide through a slot, and the slot simply allows too much play. I've seen the plates misaligned by 2-3mm during my adjustments. That may not sound like much, but it was enough to totally destroy the vertical *and* horizontal balance in a rig that was just a tiny bit out of horizontal balance!