Rigging Kino's to Ceiling

Kevin Rasmussen · March 30, 2008

Hello everyone.

Have a shoot coming up that I will be Key Grip on, not shoes I'm used to walking in as I'm usually behind the lens so I've got some concerns with the rigging I'll be doing.

The location in question is a "bank" interior, high (about 17 ft) ceilings, with fluorescent fixtures built in to the typical office ceiling. By "typical office" ceiling I'm referring to the very light, removable boards that rest on strips of metal. The DP wants to rig about 12 large 4 bank kino's up there because there is no safe area, we'll be seeing ever corner of the place so stands are out of the question.

I've never rigged anything bigger than a 150w arri to these types of ceilings and want to check in here as to the safest way to rig this set up. What clamps should I use and should I be ratchet strapping them down, or tying them off for extra safety somehow?

There WILL be actors underneath and don't want any disasters on my first key grip gig, even a light falling on the other end of the set might scare the mostly senior cast into heart attacks and we can't have that on the first day of shooting can we.

Thank you all in advance.

Cheers,

Walter Graff · March 31, 2008

With that many fixtures no drop ceiling should be used as a grid by itself. I would drop wood or light pipe battens from the fasteners the ceiling wiring is attached to and attach your fixtures to that if those fasteners are themselves secure. Normally with one or two fixtures one can attach to the metal frame of the drop ceiling on a rail that runs the length of the room and then safety to the studs in the ceiling that the drop ceiling is fastened to. Don't let anyone here or anywhere else tell you to try that with what you propose. I worked on a job where we hung three kinos to a drop ceiling in a 40x50 computer room for a next day shoot. No one bothered to see how well the drop ceiling was hung to the actual room ceiling. The next day when we came in there was a catastrophic failure of the drop ceiling system and every single bit of it fell to the floor. Drop ceilings are often hung to hold themselves up and that weight is evenly distributed. You don't want to rely on them in any way as being a simple way to hang fixtures without seriously looking at how they were fastened themselves or how sturdy their support construction is. Traditionally they are hung to a hard ceiling with wires tied to studs in the cement then wrapped around the rails of the floating system. The key is to look at how well those wraps are done to the rail. Often they are only a few turns and any isolated weight can and will make them loosen since they are often light metal wire, or even rip through the metal frame of the ceiling with too much weight. And now you will get all sorts of suggestions as to how to do this, some from experience, and most guessing. Just remember the safest rule of thumb is hang and secure everything as if you were going to be leaving it up permanently knowing that it could be hit, pulled, and come into contact with people, even if it is 17 feet off the ground. I will not try to tell you how to hang such a system because wihtout seeing it, it would be wrong for me to try. I'll just tell you that each fixture needs to be more than loosely safetyed if attached to a grid ceiling, more like fastened to the grid but also taugthly fastened to the ceiling the grid itself is fastened to with that many fixtures.

Hal Smith · March 31, 2008

Do I understand that there are existing fluorescent fixtures in the ceiling? Can you change out the bulbs for Kino bulbs, GE Chroma 50's, or similar bulbs? The only "gotcha" is you'd have to use HMI safe frame rates and shutter angles since the building's fluorescent fixtures are most likely using magnetic ballasts.

Kevin Rasmussen · March 31, 2008

Thanks Hal, Walter,

I just took a good look up there and there's no way I'm hanging even one light from that ceiling, the building is too old, visible cracks where the wire's are attached to the cement ceiling, and I'm not going to add 70 kgs of Kino, I've told them it's not an option.

We're looking at re-bulbing Hal but I'm not sure these fixtures will be compatible, they've got a new version of "energy efficient" compact flourescent bulb in them and the head connectors look smaller than kino bulbs, they're brand new fixtures, I'm contacting the manufacturer now. We might do tests and gel our 6k HMI par (Key Sunlight) accordingly allowing us to use the existing fixtures as they stand.

My measurements put pole cats out of the question.

kevin

Gus Sacks · March 31, 2008

And just gaffing the bulbs to the ceiling would be a no-no? I know the ballast's got to go somewhere, but that's not nearly 70kgs of at all.

Kevin Zanit · March 31, 2008

You could try a lot of tape and just the globes and harness like the above said, done that in a pinch before.

Also, it sounds like the fixtures that exist are using T8 globes (most Kinos are T12). Luckily Kino Flo just started making their "true match" type globe in T8 size.

Kevin Zanit

Michael Nash · March 31, 2008

You could try a lot of tape ...

Or bailing wire to the metal strips. Use blackwrap or even tape for skirts if need be.

Hal Smith · March 31, 2008

We're looking at re-bulbing Hal but I'm not sure these fixtures will be compatible, they've got a new version of "energy efficient" compact flourescent bulb in them and the head connectors look smaller than kino bulbs, they're brand new fixtures, I'm contacting the manufacturer now......

Actually that's encouraging, being modern fixtures they just may have electronic ballasts in them. Can you beg, borrow, or steal (ok, rent) a flicker meter?

April 17, 2008

Switching out your the bulbs should be your best bet if you really don't want to rig anything to the ceiling. Those modern fixtures are compatible with Kino tubes, although in my experience they put out a lot less light than with a proper ballast.

The ceiling you are talking about is called a Drop Ceiling, I personally was able to rig 650w fixtures to drop ceilings using Scissor Clamps. Although I am not sure what condition your ceiling is in so I would definitely take a look at what condition the supports/ crossbars are in.

Also I always attached the clips where the crossbars met and were attached to the ceiling, everything was very safetied off and gaff tape was wrapped around the clip/bar to make sure it could not come undone.

Best of luck to you

Scissor%20Clamp.jpg

Kar Wai Ng · April 17, 2008

If the fixtures are indeed T8, you still have a few options for tubes. I'd recommend the Philips TL-950 tubes for 5000K, or TL-930 for 3000K. Because of their high CRI (98 and 95), they're less efficient light-wise (less lumens per watt) than what's currently installed, but they do look very clean. You can rent the tubes at Whites.

Wilkin Chau · April 22, 2008

Switching out your the bulbs should be your best bet if you really don't want to rig anything to the ceiling. Those modern fixtures are compatible with Kino tubes, although in my experience they put out a lot less light than with a proper ballast.

The ceiling you are talking about is called a Drop Ceiling, I personally was able to rig 650w fixtures to drop ceilings using Scissor Clamps. Although I am not sure what condition your ceiling is in so I would definitely take a look at what condition the supports/ crossbars are in.

Also I always attached the clips where the crossbars met and were attached to the ceiling, everything was very safetied off and gaff tape was wrapped around the clip/bar to make sure it could not come undone.

Best of luck to you

For Drop Ceilings I prefer using 2X4 (most guys use 1X3) wood, about 5 feet in length and use that in the ceiling with a 750 baseplate screwed into the wood. A couple of number 3 pony clips and you're good to go. I prefer it over scissor clips since it's easier to tweak the light without risk of it falling. Plus you can position the light a lot easier with 2X4 or 1X3 wood.