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#1 mchurgin

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Posted 16 March 2012 - 05:06 AM

I have a Glidecam Xr-1000 for a bout three weeks now. Setup is a small Panasonic camera about 3/4lb with added flat plate weight and weight and QR under the camera totaling 2.5lbs.

I have tried every possible configuration and balancing act including setting camera on 2x4 platform to create a bigger footprint. Footage is stable and glides nicely except when walking forward. Any speed , slow, med fast whatever.
What I get is a thrusting forward with every step. it is not an up and down, I don't think it is acutualy "seeing my footsteps". It's like a slight bouncing. I cant see any movment in the camera or the LCD screen while walking. Objects at the edge of the frame are even more exagerated. If I stop and pan or take a few steps to the side it looks good. Only walking forward does this happen. Tom Howie of Glidecam has provided me with excellent service and support and he feels it is do the small camera. (I dont know if I understand that) Thats why I tried larger footprint etc.

I want to see if anyone has experienced this and if you guys have any solutions. I will be shooting construction, property and realestate so most videos will not have moving subjects but mostly slow touring of indoor and outdoor spaces with objects that seem to bounce forawrd and back while walking towards them. Do not confuse this with side to side sway or front to back rocking. That is not what is happening, everything is very stable with a 2.5 drop time. I've also tried every drop time between 2-3 seconds.

The Gimbal has also been calibrated to ensure that it can hang level in each direction.
If I punch the camera back and forth in the air it does not rock or show signs of this forward moving.

Any thoughts?

Thanks
for your help

Edited by mchurgin, 16 March 2012 - 11:03 AM.


#2 Norbert

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Posted 16 March 2012 - 07:25 AM

May be streaming air on the flipout display. I has this effect with a small panasonic camera too. Never had on large setting over 10 lbs.

#3 mchurgin

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Posted 16 March 2012 - 08:04 AM

May be streaming air on the flipout display. I has this effect with a small panasonic camera too. Never had on large setting over 10 lbs.


Why would that be different then streaming air over the rest of the camera body? Or any camera for that matter.

#4 Pascal

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Posted 16 March 2012 - 01:11 PM

Because the XR1000 has very little mass, you need to be very delicate in regards to operator input. A thrusting motion seems very likely to be caused by operator input.
But to be sure, have you turned off the camera's internal stabilizer? Cameras can react funny when they're on a stabilizer with the IS turned on.

If it is turned off then you really need to minimize your own hand movements as well. Because of the low mass, operator movement can easily get translated to the rig.

#5 mchurgin

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Posted 16 March 2012 - 01:45 PM

Because the XR1000 has very little mass, you need to be very delicate in regards to operator input. A thrusting motion seems very likely to be caused by operator input.
But to be sure, have you turned off the camera's internal stabilizer? Cameras can react funny when they're on a stabilizer with the IS turned on.

If it is turned off then you really need to minimize your own hand movements as well. Because of the low mass, operator movement can easily get translated to the rig.


I have tried it with IS on and off no change.

#6 Norbert

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Posted 18 March 2012 - 04:43 AM

Why would that be different then streaming air over the rest of the camera body? Or any camera for that matter.


Because the flipout display is like a sail and push the sled sideways or up.

#7 mchurgin

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Posted 18 March 2012 - 07:54 AM

Because the flipout display is like a sail and push the sled sideways or up.


Then why wouldn't that effect any size camera in balance.

Edited by mchurgin, 18 March 2012 - 07:55 AM.


#8 Norbert

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Posted 18 March 2012 - 08:22 AM

Because of the momentum of bigger mass of bigger cameras ;-)

#9 mchurgin

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Posted 18 March 2012 - 01:11 PM

Ok, so if that is actually the case why didn't mounting the camera on a piece of 2x4 the size of the platform with the add'l weights totlaing approx. 2.5-2.75 lbs plus the larger mass of the 2x4 show any better results? And what can i do about it?

Thanks

#10 Norbert

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Posted 18 March 2012 - 03:20 PM

My sled is around 16 lbs and has no windshield at the side.

#11 Pascal

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Posted 22 March 2012 - 01:49 PM

Can you post a link to some footage? It might help to find out what's going on :)

#12 mchurgin

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Posted 23 March 2012 - 06:28 AM

Can you post a link to some footage? It might help to find out what's going on :)



Here is a sample. Note that as you approach objects or those at the side the bouncing becomes very pronounced. No weight, balance or droptime changes make it better.
Any thoughts?



#13 Norbert

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Posted 23 March 2012 - 07:25 AM

Here is a sample. Note that as you approach objects or those at the side the bouncing becomes very pronounced. No weight, balance or droptime changes make it better.
Any thoughts?



It's you :-)

You make a lot of microadjustments all the time. At the white fence I could easy saw your little up and down. Try to hold the stearing hand of the sledge with a very light touch. Your legs are the source of the issue. Your walking bounces go as a wave through your whole body until it reaches your fingertips. Don't let the wave control your fingertips. If you wan't to accelerate the effect, zoom in with your camera and try to minimize the wobbling. Practice, practice.
It's more easy with bigger cameras. I do record 40 minutes of footage, until I noticed that my zoom objectiv was nearly at 80mm. I had the same problem like you, cause I walking a lot in that time.

#14 mchurgin

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Posted 23 March 2012 - 07:43 AM

It's you :-)

You make a lot of microadjustments all the time. At the white fence I could easy saw your little up and down. Try to hold the stearing hand of the sledge with a very light touch. Your legs are the source of the issue. Your walking bounces go as a wave through your whole body until it reaches your fingertips. Don't let the wave control your fingertips. If you wan't to accelerate the effect, zoom in with your camera and try to minimize the wobbling. Practice, practice.
It's more easy with bigger cameras. I do record 40 minutes of footage, until I noticed that my zoom objectiv was nearly at 80mm. I had the same problem like you, cause I walking a lot in that time.


So I think you are saying I don't walk properly. I have the camera on its widest angle 28mm. I did increase the zoom once and saw it was greatly magnified. I am trying to glide (no pun intended) while I walk. Any tips on how to make it smooth.

I see videos of people walking rather quickly and jogging that are very smooth. How?

Edited by mchurgin, 23 March 2012 - 07:44 AM.