View Full Version : Which steady cam with Letus35 flip enchanced + DVXA?
Somnang Vann September 13th, 2006, 10:14 AM Morning everyone, I'm looking to get a steady cam and I'm considering something like glidecam 4000 or a similar steady cam. I also have cavision rods as support. I don't know what the total weight is, but would glidecam 4000 be able to support or balance the DVX with all that stuff? Anyone have any suggestions on steady cams? Thanks
Yasser Kassana September 13th, 2006, 10:39 AM Try the indiecam.com.
Ben Winter September 13th, 2006, 10:42 AM 35mm adapter on a steadycam is tricky because you have to focus manually and touching the camcorder that much essentially renders the steadicam useless. I don't think 35mm + steadicam is the best idea unless you plan on shooting stopped down for deep dof so you don't have to focus, of course this makes the adapter pointless. Also a wireless FF is an option but you need gears and this whole setup is $10k+ I'm sure...yuck.
Ash Greyson September 13th, 2006, 07:47 PM If this is your plan, you need to look at the P&S unit or the Movietube, the cheaper units are not really made for adding expensive focus controllers, etc. You are looking at a minium $15K here to fly a unit and be able to control the focus (an absolute must).
ash =o)
Michael Maier September 14th, 2006, 04:47 AM Try the indiecam.com.
What's there? The link is a dead end.
Frank Hool September 14th, 2006, 07:07 AM Dennis Wood made some experiments (http://www.dvinfo.net/conf/showthread.php?t=74791) with his Brevis.
Bob Hart September 14th, 2006, 09:37 AM You might like to try spring return assisted bowden cable actuation for lens focus. - Think motor cycle throttle cable and a fabric band or non-stretching rubber strip wrap around the lens barrelworking under tension against the throttle handgrip, or a long shutter release cable with push button, likewise spring return assisted, in this case working under pressure against the push button.
The latter should be robust enough to work many popular autofocus lenses like Sigma 28mm which offer little resistence to focus movement in manual modes
The cable must travel to the lens via the center pivot point then be secured to the post up high or sled before being led to the lens barrel
It is rather inelegent and imprecise and the changing tensions of the cable will still tend to affect the float of the steadycam when older heavier manual focus lenses with stiff focus mechanisms are used.
Henry Clayton December 20th, 2006, 06:39 PM Would a follow focus with a long whip extension do the trick?
Charles Papert December 21st, 2006, 03:29 AM Herein lies an issue that I foresee as being a hefty one that will become epidemic once the full-size sensor cameras (RED and beyond) come on line.
Pulling focus in the 35mm format for Steadicam is both technically and artistically complicated. Technically in that the motors used must have a good amount of torque for the reasons Bob mentioned, and that a reliable and accurate wireless system is a must unless soft shots are to be considered acceptable. Artistically in that even if one owned a Preston or comparable high-end lens controller that meets these standards, it must be used with a certain degree of proficiency that takes years to master, or the result will again be soft shots.
I would consider a mechanical drive to be unsuccessful--Bob's suggestion of a cable driven system would be too inaccurate and unresponsive for most shots, and Henry's suggestion of a long whip would assert too much influence on the stabilizer itself. This would be the case even with a full-size rig, and thus would be even worse with a smaller camera and rig such as most users will be using.
There are various folks working on an inexpensive wireless system out there; my assumption is that the current ceiling of approximately $4000 for a single channel BFD and M1 motor could be broken assuming that the builder cut most of his profit out as is the case with various of the 35mm adaptors out there.
This still leaves the necessity for focus-pulling skill, or perhaps a greater acceptance of soft shots. I've seen a number of examples of video posted by 35mm adaptor users that contain a "searching" aesthetic, where the subject moves, then the focus springs into action, moving past the mark and then back again into focus. Again, if this sort of thing is considered acceptable by the filmmaker, then they will likely be satisfied by whatever solution is introduced.
Cory Lange December 21st, 2006, 11:34 PM I've used the Letus35FE and the DVX on a glidecam 4000 before. I Haven't tried it with rails, but with the Letus you don't really need them.
Of course there is no pulling focus, especially on a small rig like this. You just have to set your focus and keep you respective distance.
Here's a short that I shot with this setup for a kids school project, It was early, I wasn't into it, hence the gnarly dust on the GG.
It's a little heavy, but you just gotta muscle thru it. I shot this with a 28mm/2.8 lens.
http://www.youare.tv/watch.php?id=2002
Bob Hart December 24th, 2006, 01:55 AM As Charles correctly points out, a cable system would not be accurate. Preset focus limit stops would have to be used and fixed for each setup and the spring return allowed to provide the operating energy, not the cable.
This would negate the very purpose the steadycam was conceived for, flexibility, versatility and mobility, divorcement from that vexing wedlock to the fixed mount.
Wireless is really the only way to go. Maybe some form of optical IR remote like a TV controller could be tried. but this would bring its own issues through having to be aimed along a direct sight line.
A wired system might be workable using tazer wires or fine loudspeaker cables in the path across the pivot, but this would require complicated relay sytems as the cables would not be able to supply usable power, only signal level currents.
Tazer wires themselves would be inclined to be easily damaged and snag on things. fine speaker cables are not insulated so it would be impracticable to use a ground return via the sled and post structure itself.
If there was another effective and cheaper way to do it, the industry surely would have found it by now.
Diego Galvez January 2nd, 2007, 10:52 AM There are various folks working on an inexpensive wireless system out there; my assumption is that the current ceiling of approximately $4000 for a single channel BFD and M1 motor could be broken assuming that the builder cut most of his profit out as is the case with various of the 35mm adaptors out there.
Hi there,
we are attempting to build such an economy wireless remote focus system. We plan to do it via R/C and a digital servo. If we succeed with the tests, our goal is to break that ceiling more than a half.
It should be a reliable wireless focus pulling system to operate the lens when using a 35mm adapter + steadicam (stabilizers in general).
You can find all the info of the project and find out how we started here:
http://remotefollowfocus.googlepages.com/
And the progress:
http://remotefollowfocus.googlepages.com/progress
You can ask/discuss/collaborate/contribute just by contacting us at:
remotefollowfocus [at] gmail [dot] com
Hope to bring you some good news in a little time.
Greetings!
Diego Galvez
Dennis Wood January 3rd, 2007, 11:12 AM Charles, we have a wired remote system in working prototype stages for crane/jib/dolly use with a 35mm adapter. Just curious, in the world of steadicam, what (if any) level of trailing cables etc. would be considered acceptable? I'm sure I've seen cable "tenders" walking behind steadicam operators in clips, but I've never seen if the cables go to the rig itself. We are considering porting our current design to a wireless alternative, but this will take more work.
Charles Papert January 3rd, 2007, 12:20 PM Hi Dennis:
This is sort of a tough question to answer. "Acceptable" to which level of stabilizer operator...cables are always best to avoid whenever the technology allows. This means that in today's HD production world, it's not unusual to be tethered via HD-SDI back to the monitor even on big features; it's a pretty major annoyance but one that for the time being must be accomodated at the request of the DP. When it comes to lens controls, since we have had wireless in this area for 20+ years, a wired system would definitely not be considered acceptable.
In the DV/low budget world, if the wired system was substantially cheaper than the wireless system, I'm quite sure that the budget-conscious majority would find this "acceptable", somehow! The irony is that the smaller your flying mass, the more influence a given cable can have on the stability of the rig and thus it should really be even more of an issue.
As indicated here, Diego and probably others are hard at work on lower cost wireless systems than the ones out there. I would definitely suggest that your wired system incorporate the lightest and most flexible cable available. Sometimes these two parameters are at odds; the lightest cable may actual be stiffer due to internal construction. I would go with the most flexible under these circumstances.
Bob Hart January 3rd, 2007, 09:52 PM Sometimes a stiff wire can be better if it is coiled like a long spring and supported on very short standoffs across the pivot point, maybe even a full 360 degree or even 720 degree wrap.
Although it will still offer a mechanical resistance, this resistence will alter far less over a range of movement than a simple hanging wire which might get caught up on something and pull up short.
A coil is also is less likely to form its own pendulum by dangling and upsetting the balance.
Dennis Wood January 3rd, 2007, 11:22 PM On the wire issue, I was thinking exactly of the mass issue...the larger rigs have more mass, therefore likely less of an issue with cables. The cable that ties the focus unit to the control unit is currently CAT6 network cable (to allow low cost extensions) and is fairly light, and flexible (no coils though Bob). We've got the control unit mass under 600 grams or so, to keep it usable on smaller stabilized rigs. I'm not sure we can do a wireless version at the current price point though.
In any case, I'll need another few months in the gym regardless of any focus devices. It's hard to pull focus when the camera operator is face down on the ground hyperventilating :-) I'm going to predict steadicam operation will be the next big Hollywood workout craze next to pilates.
Henry Clayton January 6th, 2007, 01:11 AM The irony is that the smaller your flying mass, the more influence a given cable can have on the stability of the rig and thus it should really be even more of an issue.
Charles & others in the know:
Wouldn't it be possible to counteract this particular problem--low flying mass--by the augmentation of rinky-dink (weightwise) cameras with extra mass? Some bags with lead pellets in them, in other words?
Charles Papert January 6th, 2007, 01:30 AM Lead is the right idea, but not in bags that can shift as you tilt the camera. I myself have an 8 lb lead plate that I've used under medium weight cameras; I know of others who have chunkier plates that will convert the average 1/3" camera to the mass of a light 35mm camera, so that it can be flown on a full-size rig with the proper performance.
Optimum weight is a personal choice. I believe that a camera package around 24 lbs is as light as I'd want for most feature-type work (but for concerts or running shots, could be as light as half that). A rig that weighs quite a bit less will always be more "touchy" or "squirrely", and in some ways harder to operate.
With a small rig, there is always the problem of maximum payload (my rig will manage an IMAX camera and yes, I've been there done that!) so each system has it's preferred setup...those who own Tiffen Flyers, for instance, might have to strip a camera down to keep the arm afloat.
Charles Papert January 6th, 2007, 01:34 AM Incidentally, here's (http://www.e2etech-secure.com/cgi-bin/site16/WMCshop.cgi?action=dbview&id=wp1) a commercially available series of weight plates. Also check out the link to their cage, which is a setup we have long used at the workshops or at home when practicing with a little handheld camera or surveillance camera.
|
|