Welcome to our community

Be a part of something great, join today!

Register Log in
  • Hey all, just changed over the backend after 15 years I figured time to give it a bit of an update, its probably gonna be a bit weird for most of you and i am sure there is a few bugs to work out but it should kinda work the same as before... hopefully :)

Steadicam Group Buy - Select your model

Steadicam Group Buy - Select your model

  • Total voters
    102
David Kellermann said:
I think Tom Wills explained somewhere, that arms are mostly ise-elastic only at a certain weight. So that even most iso-elastic arms must be used with a special payload to react this way. Sorry Tom if I misquote you.
Click to expand...

I know this was posted a bit ago, but since I like discussing technical things, I figure I'd clarify some things about "Iso-elasticity". Your quote is accurate, but it is a bit of a simplification.

First of all, yes, Iso-elastic is a marketing term created by Tiffen (Cinema Products, actually, but Steadicam nonetheless), and trademarked. So, no other manufacturer can use it to describe their rigs (which is why Glidecam refers to their arms as "Dyna-Elastic"... yeah...)

What Iso-elasticity describes is an arm that requires little force to boom. Some Steadicam arms, like the tried-and-true 3A (the design which the ProLine is based off of), required quite a bit of force to boom up or down significantly. The amount of force required went up as the arm was adjusted for lighter loads, and went down as the arm was adjusted for higher loads. For this reason, the 3A was offered with different set bis of springs, which allowed you to have a spring set that would cover the cameras you needed to fly, while keeping the rig towards the top of the springs' weight range.

Newer arms are generally designed with more high-tech materials and physics, and require less force to boom up and down, but the details of how arms will perform, and what kind of force will be required to boom, depends on the geometry of the arm, the metals used in the springs, and the mechanics of how everything is put together. Some arm designs, like the one used by Liang and several other Chinese manufacturers, will require more force to boom up and down as they take more weight. The ProLine's design should be the opposite - less force to boom as the sled gets heavier. In comparison, all of the lower-end Steadicam arms at the moment have little change in the boom force required through their entire weight range (probably just a few ounces difference, and no more than a couple pounds total). Steadicam's current higher-end arms are tunable for the level of force required to boom, and that can be anywhere from ounces to several pounds.

All of this is pretty abstract though, and the thing to remember is that there are many operators today who still fly 3A arms (and even older arms sometimes!), and get beautiful shots with them. The force required to boom the rig should make absolutely no difference in the stability the shot. Sure, it's a bit easier for the op to boom with an arm that requires less force, and possibly you can finesse the rig a bit more, but the difference should not be significant.

A quick tip for working with an arm that has the kind of boom forces that the ProLine has: Set the arm so it floats a little low. Don't be afraid to carry a tiny bit of weight. It may help you avoid seeing footsteps in the shot a bit more. Also, if you know you're going to have to boom down significantly during a shot, turn the arm down a bit, and hold it up for the higher portion of the shot. It's easier, and more intuitive to hold the rig up a bit, than push it down.
 
All excellent info and advice. I hope the proline buy goes through so I can take it to heart and try it out for myself. Thanks for the insight. People like you make this place great!
 
Thanks for very useful info, Tom.

Some arm designs, like the one used by Liang and several other Chinese manufacturers, will be iso-elastic only in the bottom third or so of their weight range, and get progressively harder to boom up and down as they take more weight. The ProLine's design should be the opposite - less force to boom as the sled gets heavier
Click to expand...


Can you tell the the reason why such difference in behaviour happens?

P.S. Laing is providing different springs sets for current arm.

And also work on few high end arm designs now.
 
Vitaliy Kiselev said:
Thanks for very useful info, Tom.

Can you tell the the reason why such difference in behaviour happens?

P.S. Laing is providing different springs sets for current arm.

And also work on few high end arm designs now.
Click to expand...

Vitaly,

The difference in performance is based upon the number of springs used, the metal composition of the springs, the way they are attached inside the arm, and the geometry of the attachment points (which is the most important part). While I don't know how the springs in the Liang arm and similar perform based upon their compositions, I can see looking at the geometry of the arm roughly how each will perform.

There's some relatively complex physics involved, and also quite a few patents (which I do respect, as someone who designs much of my own gear, and may be looking into patents eventually), so I'm not going to go into exactly how a perfect iso-elastic performance is obtained, however.
 
The difference in performance is based upon the number of springs used, the metal composition of the springs, the way they are attached inside the arm, and the geometry of the attachment points (which is the most important part). While I don't know how the springs in the Liang arm and similar perform based upon their compositions, I can see looking at the geometry of the arm roughly how each will perform.
Click to expand...

Hmm, interesting, as from pure physical pov and modelling, with increase of weight, Laing design arm performace become not worse, but better.

There's some relatively complex physics involved, and also quite a few patents (which I do respect, as someone who designs much of my own gear, and may be looking into patents eventually), so I'm not going to go into exactly how a perfect iso-elastic performance is obtained, however.
Click to expand...

I asked for factual foundations of your opinion.
 
Vitaliy Kiselev said:
Hmm, interesting, as from pure physical pov and modelling, with increase of weight, Laing design arm performace become not worse, but better.
Click to expand...

While the arm may feel better with more weight on it (as a rig often does), because of the mechanics and geometry of the spring adjustment mechanism, the spring will progressively need more force to boom up and down as the arm adjustment screw is moved upwards. Unless there's some magic mechanics in there that aren't visible in the pictures you've posted (and I've studied the pictures pretty closely), this is simply how the physics work out.

As I said in my big post, the force required to boom isn't that big of a deal for rigs at this price range though. So, if the arm performs well at higher weights, that's a good thing, even if it's not with low booming force.

Vitaliy Kiselev said:
I asked for factual foundations of your opinion.
Click to expand...

I understand, however I just wanted to mention that I'm not going into the physics of why this works, or the tricks that Tiffen is using, rather than have anyone ask about it.
 
I just logged into your blog to find the deadline for ordering. I don't see it there. On the original post there are mentions of March 31 and March 28. Is tomorrow the deadline? If there is flexibility I wonder if it would be better to wait until after 4/15 (tax day).
 
because of the mechanics and geometry of the spring adjustment mechanism, the spring will progressively need more force to boom up and down as the arm adjustment screw is moved upwards. Unless there's some magic mechanics in there that aren't visible in the pictures you've posted (and I've studied the pictures pretty closely), this is simply how the physics work out.
Click to expand...

In such arms adjustment of spring is such that with more spring tension position of the spring becomes more like paralellogram diagonal. And, in fact it is whole point of 3 springs design to keep diagonal despite the different tension (so called Z design).
For static it is not really such important, it is exactly for more even boom force.
 
David,

Is there any chance Luciano could allow a deposit to hold a place in the order for those whose funds haven't come together quickly enough. This isn't asking for a payment plan and the deposit could be nonrefundable to show that people are serious. Say 20%. If I knew this was possible I could make the deposit and have my funds in approximately two weeks and I would definitely participate. Perhaps give a generous amount of time during which time anyone with that situation could reasonably be expected to overcome whatever obstacles. Perhaps a month or by time of shipping.

I don't think there is a downside to this for the company and it might ensure the participation of those who can't bring the funds together in time.
 
Steven Blye said:
David,

Is there any chance Luciano could allow a deposit to hold a place in the order for those whose funds haven't come together quickly enough. This isn't asking for a payment plan and the deposit could be nonrefundable to show that people are serious. Say 20%. If I knew this was possible I could make the deposit and have my funds in approximately two weeks and I would definitely participate. Perhaps give a generous amount of time during which time anyone with that situation could reasonably be expected to overcome whatever obstacles. Perhaps a month or by time of shipping.

I don't think there is a downside to this for the company and it might ensure the participation of those who can't bring the funds together in time.
Click to expand...

pm sent. If someone else is in this situation, please send me a message.

Cheers
David
 
Hey guys,

I'm new to the forum but have been reading it for quite some time. This group buy really peaked my interest. Right now I'm shooting privately on a 5DMKII but will have access to a Scarlet without too much of a fuss. I've been going back and forth in my mind about whether to invest in a shoulder rig (kind of allergic to the lack of stability that goes with this kind of shooting) and after having recently shot on a cheap steadicam (have used both Wondlan and Magiqcam) I'm quite impressed with the results after some practic. The Magiqcam especially is a nightmare to dial in and has very bad support for universal monitor and battery mounting and so on but other than that the footage looks quite good (much much better with a heavier camera) and those rigs are in the same price range as a complete shoulder rig with good quality so I'm thinking I might just invest in a steadicam instead.

The tests you guys have done have helped immensely and I'm wondering if it's too late to get in on this group buy, provided the price is right?

Best Regards,
Oscar
 
You must log in or register to reply here.
Back
Top