Gear head at DVinfo.net

David Mesloh · February 19th, 2003, 11:10 PM

I'm looking to make a gear head for my tripod. Any suggestions? Anyone ever try this? I'm have a serious amount of machining background. I'm not intimidated by the project, just the design details that I might miss.

What do you think Charles? Am I nuts? I just want more control over my pan and tilt than using a fluid head.

David

Ken Tanaka · February 19th, 2003, 11:26 PM

By "gear head" what do you really have in mind? A gear mechanism to pan and tilt on the tripod?

David Mesloh · February 19th, 2003, 11:48 PM

Yep, Same as the Panavision Pan/tilt heads.

I built motion control pan/tilt heads for Dreamquest Images many years ago. Those were with stepper motors and Berg belts.

In all actuallity, I'd like to prototype a head that could be manufactured for a reasonable cost for use with DV cameras.

Ken Tanaka · February 19th, 2003, 11:56 PM

Hey, it sounds like you're the guy that can do it. Charge-on! If you can keep it under $500 for a design load range of 4-12lbs you'll have many orders.

Ken Tanaka · February 20th, 2003, 12:07 AM

BTW, you probably already know this, but Varizoom already makes a motion control head (the VZ-MC100). It's darned expensive but reportedly well designed.

Wayne Orr · February 20th, 2003, 10:20 AM

I don't know why you want to build a gear head, but if your purpose is to imitate professional camera operation, you will find more and more cameras used in film operated with fluid heads. The improvement in design of the fluid heads combined with the smaller cameras make for a very popular combination. In fact, famed Director of Photography, Vitorrio Starraro insists that his operator use a Vinten fluid head on all his projects. His claim is that the fluid head makes the camera more "organic" with the operator.

But have fun with your project.

Charles Papert · February 20th, 2003, 11:26 AM

Well. European DP's in particular have a fondness for fluid heads, and I have often heard the "organic" term bandied around. After growing up with fluid heads then learning the "wheels" i.e. gear head about nine years ago, I feel comfortable saying at this point that if properly operated, it should be impossible to tell which head is in use from looking at the results. I prefer a gear head for most kinds of shooting, switching to the fluid head for whip pans, extreme tilts, self-operated zooms (yup, in the film world it is often the camera assistant who works the zoom, I know it seems alien to most of you!) and fast, unpredictable motion. Dolly shots in particular are where the gear head shines, as starts and stops can often cause bumps in the photography with a fluid head (your body inertia results in involuntary tilts). Also it is easier to dial in slow continuous movements. I know many operators who have different preferences, but rarely do I see those who are completely comfortable and competent with the wheels opt exclusively to use a fluid head instead, if you see what I am getting at.

As far as building your own, David, I am fascinated to see what you come up with. There's quite a bit of elegant mechanics in there, for it to work well there needs to be an absolute minimum of backlash plus a nice smooth gear shift mechanism. Reverse engineering an Arrihead would be a good start! I would recommend attempting to build it using a L bracket support design rather than the classic arcing design, in other words a nodal tilt mechanism which means greater tilt range than the 60 degrees usually found in a classic gear head.

Ken, I was startled to hear that Varizoom offered a motion control head, then I looked at the page. I would designate that as a "remote head", whereas a motion control head allows for programmable and repeatable moves, which would be a fantastic bargain for $3000, and I'd write a check today if it were the case!

Ken Tanaka · February 20th, 2003, 11:48 AM

Aha. So for nomenclatural clarity's sake would it be most accurate to define a Motion Control Head as a device that provides the operator the with ability to programmatically set and control the camera's movements in 3 independent axes wih respect to time? For example, acceleration curves could be set and locked-in for the camera's pan, tilt and roll.

Versus a Remote Head which permits control, but not programmatic control, of the camera's motion in 1-3 axes.

Is this pretty close to a reasonable working distinction?

David Mesloh · February 21st, 2003, 12:24 AM

Thanks Ken and Charles. Charles, I hadn't even considered an L-Bracket with nodal axis. That sounds like a couple of anti-backlash worm gears and a few handles.

I also have a feeling that the gear head needs to have some mass to it so that while turning the handles, you don't cause the tripod to move.

Most of the heads I have seen have been mounted on a dolly or maybe a high hat mounted on the ground. I don't recall seeing a head mounted on sticks very often. The construction of the arm on a dolly is incredibly robust. That helps isolate vibration as well.

Hmmmmmmm.....................................

David

Zac Stein · February 21st, 2003, 12:44 AM

If you get one of these built i would buy one for sure if they are very cheap. Or i would promote it around my town and get the shops onto you in exchange for a unit.

Zac

Ken Tanaka · February 21st, 2003, 12:54 AM

Kermie,
You can be sure that what David's thinking about ain't gonna be cheap! <g>

Zac Stein · February 21st, 2003, 12:56 AM

Ken,

Heh that is why i suggested another way, i know a few camera stores here that would prob buy into them and get a few, they got some skycranes after i put them onto them.

zac

Rob Lohman · February 21st, 2003, 03:39 AM

Ken,

Motion Control is not only used to control camera(s) but
also models, objects, cranes and other things. One of the
more interesting things is that it can repeat a motion exactly
same everytime to photorgraph different layers or do other
effects.

But basically your definition is correct!

Charles Papert · February 22nd, 2003, 11:03 PM

<<<-- Originally posted by dmesloh@gimixfx.com :
Most of the heads I have seen have been mounted on a dolly or maybe a high hat mounted on the ground. I don't recall seeing a head mounted on sticks very often. The construction of the arm on a dolly is incredibly robust. That helps isolate vibration as well.>>>

David:

I will always work off the dolly if I can help it, mostly because I HATE levelling a Mitchell (flat base) head off sticks. Having to screw around with raising one leg, lowering the others etc. is just a royal pain compared to the quick height adjustments on the dolly. Plus having a seat is a nice way to get through those long days!

Nevertheless, I will use sticks when the location requires it for one reason or another. A solid set (Ronford makes the industry standard) is strong enough to handle the torque created by most operating situations. A geared head, incidentally, transmits less torque to the support apparatus than a fluid head.

Mike Rehmus · February 23rd, 2003, 01:06 PM

Myself being a lazy machinist (among other things), I'd look to build something a lot less expensive than a 'real' metal gear-head.

Maybe a timing belt can be substituted for the gears. A whole lot cheaper and lighter. If mass is required, it can be added where it will do the most good, not distributed over the mechanism.

Perhaps one can engineer an add-on mechanism to some of those terrible but terribly strong Bogen heads with the removable sliding plate. Lots of room for mounting sectors.

That would also make it relatively easy to add a stepper or servo drive if one needed to remote the head.

February 19th, 2003, 11:10 PM	#1
David Mesloh Regular Crew Join Date: Mar 2002 Location: Los Angeles, CA Posts: 94	Gear head I'm looking to make a gear head for my tripod. Any suggestions? Anyone ever try this? I'm have a serious amount of machining background. I'm not intimidated by the project, just the design details that I might miss. What do you think Charles? Am I nuts? I just want more control over my pan and tilt than using a fluid head. David

February 19th, 2003, 11:26 PM	#2
Ken Tanaka Retired DV Info Net Almunus Join Date: Dec 2001 Location: Chicago, IL Posts: 6,943	By "gear head" what do you really have in mind? A gear mechanism to pan and tilt on the tripod? __________________ Lady X Films: A lady with a boring wardrobe...and a global mission. Hey, you don't have enough stuff! Buy with confidence from our sponsors. Hand-picked as the best in the business...Really! See some of my work one frame at a time: www.KenTanaka.com

February 19th, 2003, 11:56 PM	#4
Ken Tanaka Retired DV Info Net Almunus Join Date: Dec 2001 Location: Chicago, IL Posts: 6,943	Hey, it sounds like you're the guy that can do it. Charge-on! If you can keep it under $500 for a design load range of 4-12lbs you'll have many orders. __________________ Lady X Films: A lady with a boring wardrobe...and a global mission. Hey, you don't have enough stuff! Buy with confidence from our sponsors. Hand-picked as the best in the business...Really! See some of my work one frame at a time: www.KenTanaka.com

February 20th, 2003, 12:07 AM	#5
Ken Tanaka Retired DV Info Net Almunus Join Date: Dec 2001 Location: Chicago, IL Posts: 6,943	BTW, you probably already know this, but Varizoom already makes a motion control head (the VZ-MC100). It's darned expensive but reportedly well designed. __________________ Lady X Films: A lady with a boring wardrobe...and a global mission. Hey, you don't have enough stuff! Buy with confidence from our sponsors. Hand-picked as the best in the business...Really! See some of my work one frame at a time: www.KenTanaka.com

February 20th, 2003, 10:20 AM	#6
Wayne Orr Major Player Join Date: Dec 2002 Location: Northridge Ca Posts: 734	I don't know why you want to build a gear head, but if your purpose is to imitate professional camera operation, you will find more and more cameras used in film operated with fluid heads. The improvement in design of the fluid heads combined with the smaller cameras make for a very popular combination. In fact, famed Director of Photography, Vitorrio Starraro insists that his operator use a Vinten fluid head on all his projects. His claim is that the fluid head makes the camera more "organic" with the operator. But have fun with your project. __________________ Wayne If it was easy, they'd get a relative to do it.

February 19th, 2003, 11:48 PM	#3
David Mesloh Regular Crew Join Date: Mar 2002 Location: Los Angeles, CA Posts: 94	Yep, Same as the Panavision Pan/tilt heads. I built motion control pan/tilt heads for Dreamquest Images many years ago. Those were with stepper motors and Berg belts. In all actuallity, I'd like to prototype a head that could be manufactured for a reasonable cost for use with DV cameras.

February 20th, 2003, 11:26 AM	#7
Charles Papert Wrangler Join Date: Jan 2002 Location: Los Angeles, CA Posts: 6,810	Well. European DP's in particular have a fondness for fluid heads, and I have often heard the "organic" term bandied around. After growing up with fluid heads then learning the "wheels" i.e. gear head about nine years ago, I feel comfortable saying at this point that if properly operated, it should be impossible to tell which head is in use from looking at the results. I prefer a gear head for most kinds of shooting, switching to the fluid head for whip pans, extreme tilts, self-operated zooms (yup, in the film world it is often the camera assistant who works the zoom, I know it seems alien to most of you!) and fast, unpredictable motion. Dolly shots in particular are where the gear head shines, as starts and stops can often cause bumps in the photography with a fluid head (your body inertia results in involuntary tilts). Also it is easier to dial in slow continuous movements. I know many operators who have different preferences, but rarely do I see those who are completely comfortable and competent with the wheels opt exclusively to use a fluid head instead, if you see what I am getting at. As far as building your own, David, I am fascinated to see what you come up with. There's quite a bit of elegant mechanics in there, for it to work well there needs to be an absolute minimum of backlash plus a nice smooth gear shift mechanism. Reverse engineering an Arrihead would be a good start! I would recommend attempting to build it using a L bracket support design rather than the classic arcing design, in other words a nodal tilt mechanism which means greater tilt range than the 60 degrees usually found in a classic gear head. Ken, I was startled to hear that Varizoom offered a motion control head, then I looked at the page. I would designate that as a "remote head", whereas a motion control head allows for programmable and repeatable moves, which would be a fantastic bargain for $3000, and I'd write a check today if it were the case! __________________ Charles Papert www.charlespapert.com

February 20th, 2003, 11:48 AM	#8
Ken Tanaka Retired DV Info Net Almunus Join Date: Dec 2001 Location: Chicago, IL Posts: 6,943	Aha. So for nomenclatural clarity's sake would it be most accurate to define a Motion Control Head as a device that provides the operator the with ability to programmatically set and control the camera's movements in 3 independent axes wih respect to time? For example, acceleration curves could be set and locked-in for the camera's pan, tilt and roll. Versus a Remote Head which permits control, but not programmatic control, of the camera's motion in 1-3 axes. Is this pretty close to a reasonable working distinction? __________________ Lady X Films: A lady with a boring wardrobe...and a global mission. Hey, you don't have enough stuff! Buy with confidence from our sponsors. Hand-picked as the best in the business...Really! See some of my work one frame at a time: www.KenTanaka.com

February 21st, 2003, 12:24 AM	#9
David Mesloh Regular Crew Join Date: Mar 2002 Location: Los Angeles, CA Posts: 94	Thanks Ken and Charles. Charles, I hadn't even considered an L-Bracket with nodal axis. That sounds like a couple of anti-backlash worm gears and a few handles. I also have a feeling that the gear head needs to have some mass to it so that while turning the handles, you don't cause the tripod to move. Most of the heads I have seen have been mounted on a dolly or maybe a high hat mounted on the ground. I don't recall seeing a head mounted on sticks very often. The construction of the arm on a dolly is incredibly robust. That helps isolate vibration as well. Hmmmmmmm..................................... David

February 21st, 2003, 12:44 AM	#10
Zac Stein Major Player Join Date: Aug 2002 Location: Melbourne, Australia Posts: 730	If you get one of these built i would buy one for sure if they are very cheap. Or i would promote it around my town and get the shops onto you in exchange for a unit. Zac

February 21st, 2003, 12:54 AM	#11
Ken Tanaka Retired DV Info Net Almunus Join Date: Dec 2001 Location: Chicago, IL Posts: 6,943	Kermie, You can be sure that what David's thinking about ain't gonna be cheap! <g> __________________ Lady X Films: A lady with a boring wardrobe...and a global mission. Hey, you don't have enough stuff! Buy with confidence from our sponsors. Hand-picked as the best in the business...Really! See some of my work one frame at a time: www.KenTanaka.com

February 21st, 2003, 12:56 AM	#12
Zac Stein Major Player Join Date: Aug 2002 Location: Melbourne, Australia Posts: 730	Ken, Heh that is why i suggested another way, i know a few camera stores here that would prob buy into them and get a few, they got some skycranes after i put them onto them. zac

February 21st, 2003, 03:39 AM	#13
Rob Lohman RED Code Chef Join Date: Oct 2001 Location: Holland Posts: 12,514	Ken, Motion Control is not only used to control camera(s) but also models, objects, cranes and other things. One of the more interesting things is that it can repeat a motion exactly same everytime to photorgraph different layers or do other effects. But basically your definition is correct! __________________ Rob Lohman, visuar@iname.com DV Info Wrangler & RED Code Chef Join the DV Challenge \| Lady X Search DVinfo.net for quick answers \| Buy from the best: DVinfo.net sponsors

February 22nd, 2003, 11:03 PM	#14
Charles Papert Wrangler Join Date: Jan 2002 Location: Los Angeles, CA Posts: 6,810	<<<-- Originally posted by dmesloh@gimixfx.com : Most of the heads I have seen have been mounted on a dolly or maybe a high hat mounted on the ground. I don't recall seeing a head mounted on sticks very often. The construction of the arm on a dolly is incredibly robust. That helps isolate vibration as well.>>> David: I will always work off the dolly if I can help it, mostly because I HATE levelling a Mitchell (flat base) head off sticks. Having to screw around with raising one leg, lowering the others etc. is just a royal pain compared to the quick height adjustments on the dolly. Plus having a seat is a nice way to get through those long days! Nevertheless, I will use sticks when the location requires it for one reason or another. A solid set (Ronford makes the industry standard) is strong enough to handle the torque created by most operating situations. A geared head, incidentally, transmits less torque to the support apparatus than a fluid head. __________________ Charles Papert www.charlespapert.com

February 23rd, 2003, 01:06 PM	#15
Mike Rehmus Wrangler Join Date: May 2002 Location: Vallejo, California Posts: 4,049	Myself being a lazy machinist (among other things), I'd look to build something a lot less expensive than a 'real' metal gear-head. Maybe a timing belt can be substituted for the gears. A whole lot cheaper and lighter. If mass is required, it can be added where it will do the most good, not distributed over the mechanism. Perhaps one can engineer an add-on mechanism to some of those terrible but terribly strong Bogen heads with the removable sliding plate. Lots of room for mounting sectors. That would also make it relatively easy to add a stepper or servo drive if one needed to remote the head. __________________ Mike Rehmus Hey, I can see the carrot at the end of the tunnel!