Jump to content


Photo

arri IIC 80fps


  • Please log in to reply
14 replies to this topic

#1 nathan snyder

nathan snyder
  • Basic Members
  • PipPip
  • 75 posts
  • Other
  • Boise, Idaho USA

Posted 24 February 2007 - 10:54 PM

So I have come into an arri 2c. Not my first arri camera or my first 35mm camera but this camera has a tach that reads up to 80fps. I have a need to shoot at theat speed here in the next couple of weeks. I assume that I would need the high speed motor to reach that speed, which is not a problem I halve already found one to rent. But my concern is that this is a real high speed movement camera.

My question is: How can I tell that this camera can actually safely run at 80fps and has not simply been hacked and merely hd a 80fps tach stuck onto a regular 2C?

The movement does feel a little different from my 2B when I turn the inching knob, but not a lot. There is no serial on the 2C because I think it has been modified by Techniscope (the paint is pretty fresh, it has a BNCR mount, and has a techniscope door (which is awesome!)).

Can anyone give me some advice as to whether or not this camera is safe to run at 80fps?
  • 0

#2 Hal Smith

Hal Smith
  • Sustaining Members
  • 2280 posts
  • Cinematographer
  • OKC area

Posted 25 February 2007 - 10:48 AM

So I have come into an arri 2c.

One thing to look for is adjustment screws at the top and bottom of the gate. Hi-speeds have to be adjusted for the thickness of the film stock, that's what the screws are there for. Also, standard motors won't go 80fps, you'll at least need the Arri hi-speed motor with the external speed control reostat.
  • 0

#3 Patrick Neary

Patrick Neary
  • Basic Members
  • PipPipPipPip
  • 873 posts
  • Cinematographer
  • Portland, OR

Posted 25 February 2007 - 12:06 PM

You might want to run a couple hundred feet through at 80fps (before the job) to check for registration issues.
  • 0

#4 Leo Anthony Vale

Leo Anthony Vale
  • Basic Members
  • PipPipPipPip
  • 2010 posts
  • Other
  • Pittsburgh PA

Posted 26 February 2007 - 04:05 PM

My question is: How can I tell that this camera can actually safely run at 80fps and has not simply been hacked and merely hd a 80fps tach stuck onto a regular 2C?

The movement does feel a little different from my 2B when I turn the inching knob, but not a lot. There is no serial on the 2C because I think it has been modified by Techniscope (the paint is pretty fresh, it has a BNCR mount, and has a techniscope door (which is awesome!)).

Can anyone give me some advice as to whether or not this camera is safe to run at 80fps?



My question is: How can I tell that this camera can actually safely run at 80fps and has not simply been hacked and merely hd a 80fps tach stuck onto a regular 2C?

The movement does feel a little different from my 2B when I turn the inching knob, but not a lot. There is no serial on the 2C because I think it has been modified by Techniscope (the paint is pretty fresh, it has a BNCR mount, and has a techniscope door (which is awesome!)).

Can anyone give me some advice as to whether or not this camera is safe to run at 80fps?


Do you mean Technovision rather than Tecniscope. Cameras were modified to Techniscope & Technicolor did not do the modifications. Whereas Technovision painted their cameras white and used the ECE/Fellini doors with the Mitchell S35R optics.

The gate needs to be adjusted for 80fps, but I don't know how to tell if has been adjusted.
  • 0

#5 nathan snyder

nathan snyder
  • Basic Members
  • PipPip
  • 75 posts
  • Other
  • Boise, Idaho USA

Posted 27 February 2007 - 12:25 AM

Yes, it is a technovision modified camera. I wouldn't even want a techniscope, 2 perf camera. Sorry for the mistype.

So, what I m hearing is that the only different on an 80fps 2C is that the movement is driven faster and the pressure plate has more pressure?

Hmmm... Well I gues I will try it out and see what happens. Does anyone think I will do damage to the camera if I run it at 80fps and it is just a normal 2C camera?

I am renting it out to a local outfit that shoots wildlife stock footage. Most of their stuff is 16mm so they don't know a whole lot about the high speed arri2c. They are going to shoot a blad eagle and want to use my rig. I need to make sure their will be no problems first. I guess I will be spending the next few weeks shooting short ends, watching the prints, and making adjustments, if needed, to get the camera up to speed (pun intended).

Thanks for the replies everyone.
  • 0

#6 Leo Anthony Vale

Leo Anthony Vale
  • Basic Members
  • PipPipPipPip
  • 2010 posts
  • Other
  • Pittsburgh PA

Posted 27 February 2007 - 02:27 PM

So, what I m hearing is that the only different on an 80fps 2C is that the movement is driven faster and the pressure plate has more pressure?

Hmmm... Well I gues I will try it out and see what happens. Does anyone think I will do damage to the camera if I run it at 80fps and it is just a normal 2C camera?


Trying to drive a non high speed at 80fps will probably burn the motor out.
Else the problem would be picture steadiness if the gate isn't adjusted properly.
  • 0

#7 John Sprung

John Sprung
  • Sustaining Members
  • 4635 posts
  • Other

Posted 07 March 2007 - 01:39 PM

So, what I m hearing is that the only different on an 80fps 2C is that the movement is driven faster and the pressure plate has more pressure?

Actually, it's less pressure you want. Hold the film tighter, and you can't go as fast without damaging the perfs that the claw uses. But you can't use too little pressure, either. The acceptable range gets narrower, and is near the low end of what works at 24 FPS. The rest of the moving parts also need to be balanced a little better, much like hot rodding a car engine. Going from 24 to 80 FPS, your pulldown cam is going from 1440 to 4800 RPM. On those exotic Fries 300 FPS cameras, it's an astounding 18,000 RPM. That's about the max for physical pulldown. Beyond that, it's continuous film motion with rotating prisms.


-- J.S.
  • 0

#8 nathan snyder

nathan snyder
  • Basic Members
  • PipPip
  • 75 posts
  • Other
  • Boise, Idaho USA

Posted 07 March 2007 - 07:28 PM

Hi John,

Thanks for the reply. I had actually called Cinema Engineering and asked Richard about it. What you said pretty much confirms what he said. No special movement, just precisely set stuff. His explaination of the adjustments screws on the pressure plate was to distribute the pressure evenly across the plate. He also described a method of setting the pressure were, after taking the gate out of the camera and affixed to a bench or something, film is placed in the gate with the presure plate closed and the film is attached to a tension gauge.

Anyway, it is all academic at this point. While I did find a CE highspeed motor to rent the guy shooting the pictures of the eagle decided he would just use his own 2C and run his variable speed motor up to 50fps with a couple of 12V bateries run in series.

However, I do appreciate the responses, and will keep them in mind for the future.
  • 0

#9 chuck colburn

chuck colburn
  • Basic Members
  • PipPipPipPip
  • 389 posts
  • Other
  • orygun

Posted 07 March 2007 - 10:02 PM

How we use to do it was to remove the gate, make sure it was clean ( used "Never Dull" cotton polish wadding to polish the aperture and pressure plate) then put a little "Nose Grease" on each. Take about three feet of fresh film and put the gate on one end and hold it vertically give it a little shake and the gate should slide down the film on it's own weight about a foot to a foot and a half. You can use the wadding to polish the German silver film trough that runs along the bottom of the inside of the camera too. If this "precision" test works out you should be fine for HS running.
  • 0

#10 Jizhong Zhang

Jizhong Zhang
  • Basic Members
  • PipPip
  • 27 posts
  • Cinematographer
  • Los Angeles

Posted 08 March 2007 - 07:27 AM

I saw a 80fps II c too but how to Change the motor speed?? and why the power supply adapter has three wires? and one can show me me how to connect? and I also want to know how many volt of the II c `s power supply? 12v? 24?
  • 0

#11 nathan snyder

nathan snyder
  • Basic Members
  • PipPip
  • 75 posts
  • Other
  • Boise, Idaho USA

Posted 08 March 2007 - 06:15 PM

Chuck, your story is hilarious. Would you mind if I quote you on my website?


Jizhong, the 80fps system I have been looking at uses a rheostate or a variable potentiometer (a dial that changes the amount of power going to the motor). It is not a precise system and the tachometer would need to be used to adjust the speed. And someone else could probably answer better than me but there are a few different types of motors that require different voltages. And the old standyby variable speed motor can be run a a range of voltages with any harm. I usually run mine on a 16volt battery but if it is dead I will use a 12v battery, though I have to adjust the speed control to make up for the voltage drop.
  • 0

#12 chuck colburn

chuck colburn
  • Basic Members
  • PipPipPipPip
  • 389 posts
  • Other
  • orygun

Posted 08 March 2007 - 09:33 PM

Hi Nathan,

Yeah it does read kinda goofy doesn't it ? But I was being dead serious. This was taught to me by Jimmy Beaumonte who was a camera tech, machienist and person extrodinar. He was the man who took a VistaVision movement and adapted it to run with Arri 35mm magazines which resulted in the camera George Lucas used for all the opticals in Star Wars. We called it the Empireflex!
Sure you can quote me. lol

Chuck
  • 0

#13 chuck colburn

chuck colburn
  • Basic Members
  • PipPipPipPip
  • 389 posts
  • Other
  • orygun

Posted 09 March 2007 - 01:38 PM

Hi Nathan,

I just looked over you web site. Very nice! It warms the heart of this crusty old cine tech. to see that lovely equipment. Don't EVER get rid of those Super Baltars, there is nothing quite like the look they make out there.
Speaking of hilarious.... love the Bolex in the Mitchell blimp!

Chuck
  • 0

#14 nathan snyder

nathan snyder
  • Basic Members
  • PipPip
  • 75 posts
  • Other
  • Boise, Idaho USA

Posted 11 March 2007 - 10:38 PM

Hey Chuck,
I am glad you like the site. I have lots of stuff that I have yet to get up. I really need some interns to help me out fleshing out my website. I put all of the cine stuff up on the site to help other folks out who can not find out info about the good old stuff. I can never find details out about old equipement so I end up buying it to find out. Every time I get new gear I try to learn everything I can about it (usually by taking it apart) and then I like to share that info with anyone on the web who want to know.

By The Way, I know about the Super Baltars... I wish I could get more, but I just don't have the money. I did get a dirt cheap price on two sets of baltar BNC mounts. I can't use them because all three of my 35mm cameras are now (or soon to be) BNCR mount and they all have spinning reflex mirrors. So, I have built a ground glass adaptor (BNC mount) for video cameras to make use of the Baltar lenses. I will have a webpage up about the device and the lenses soon. Even the regular Baltars are pretty good. But not as good as my Supers.

Oh, and the story about the Epireflex is great too! I will have fun telling that one to my students and grips.
  • 0

#15 Jizhong Zhang

Jizhong Zhang
  • Basic Members
  • PipPip
  • 27 posts
  • Cinematographer
  • Los Angeles

Posted 10 April 2007 - 08:49 AM

I don`t have a speed controler What can I do?
  • 0


Gamma Ray Digital Inc

Abel Cine

Glidecam

Metropolis Post

Ritter Battery

Paralinx LLC

Wooden Camera

CineLab

The Slider

Opal

Visual Products

Tai Audio

Willys Widgets

rebotnix Technologies

Broadcast Solutions Inc

FJS International, LLC

Technodolly

Media Blackout - Custom Cables and AKS

Aerial Filmworks

CineTape

Rig Wheels Passport

Ritter Battery

Abel Cine

The Slider

rebotnix Technologies

Wooden Camera

CineLab

Metropolis Post

Opal

Technodolly

Rig Wheels Passport

CineTape

FJS International, LLC

Glidecam

Media Blackout - Custom Cables and AKS

Gamma Ray Digital Inc

Aerial Filmworks

Willys Widgets

Paralinx LLC

Tai Audio

Broadcast Solutions Inc

Visual Products