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  • 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 :)

Filming near an MRI. . .

Stephen Pruitt

Stephen Pruitt

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Hey all. . .

Has anyone tried to use their RED One inside a room with an MRI? I'm not talking about an MRI in operation, which I'm sure would be dangerous, but an MRI machine.

We have a scene in our new feature where a dying man goes into an MRI machine. We'll, we need to know if it is even possible before we make the "final arrangements," as it were.

Any thoughts?

Thanks.

Stephen
 
While were at it, does it damage the sensor of a red to shoot into a microwave that is running? I am working on a cooking show as a DIT and want to buy there red, but I am not sure if the the microwave close ups might of effected the sensor chip.... Thanks!!!
 
I believe an MRI is ALWAYS on. Beware. Or dust off your film camera.

Good shooting and best regards,

Leo
 
There are large permanent magnets in an MRI. I volunteered to help a a friend with a project, and it involved a couple MRI's. The tech (with a Ph.D in nuclear physics!) took his ID badge, which was on a little tether with a tiny piece of metal, and held it in the air about 3 meters away. The thing snapped to attention and hung in the air.
Just google 'MRI accidents'. I would probably try shooting through the window, if possible...
 
That's a great question Stephen. I'll be watching this space for answers. I would expect that the machine is well shielded outside the target area, but I know no facts as to short term exposures and safety procedures within the area of operation.

Brian, I'm sure a little distance would be a simple and adequate answer to your concerns. Do you have lenses long enough to get you to where you feel safe?
 
The camera is a good 4-6 feet from the microwave...its got a cooke zoom on it... before I buy it I started to worry what the frequencies I cannot see might be doing to it..
 
Brian Merlen said:
The camera is a good 4-6 feet from the microwave...its got a cooke zoom on it... before I buy it I started to worry what the frequencies I cannot see might be doing to it..
Click to expand...

Only 6 ft.? What lens is it? It might be better to consider longer glass for close ups in general, not just the microwave.
 
Every microwave I've ever seen has a Faraday cage (the metal mesh) around the whole thing to prevent microwaves from escaping the interior. Of course, they simple don't work that well. Put a 2.4 GHz cordless phone into the microwave, and you can still make a call to it. 2.4 GHz is the domain of microwaves.
 
Stephen Pruitt said:
Hey all. . .

Has anyone tried to use their RED One inside a room with an MRI? I'm not talking about an MRI in operation, which I'm sure would be dangerous, but an MRI machine.

We have a scene in our new feature where a dying man goes into an MRI machine. We'll, we need to know if it is even possible before we make the "final arrangements," as it were.

Any thoughts?

Thanks.

Stephen
Click to expand...



My Epic survived, one of the first shoots I did with it!
 

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Obviously, Stephen, you've done it. Were there any special precautions you used??? I assume you didn't use a tripod fluid head with steel in it. Did you use one at all?

I really need to know this, as your experience sort of suggests the portents of doom may not be accurate.

Stephen
 
Stephen Williams said:
My Epic survived, one of the first shoots I did with it!
Click to expand...

I would suspect the machine was off when these were taken. Otherwise, no technician will let you near the machine when it is on. I've shot MRIs both on and off. When on, you "might" be able to be let inside the room, but probably not. Shooting through the door works or through the window, but sometimes the window has a screen mesh on it, so that presents issues. They are going to be much more concerned with the safety of the MRI than about your silly little camera and lighting equipment.

Personal story time. Shot an MRI back in 1988. It was an out-of-town trip and when I got back to town, I was trying to exit the parking lot at the airport. The machine wouldn't read my ticket for some reason. The gal in the ticket booth asked if I'd been near any magnets, then it dawned on me. Take EVERYTHING out of your pockets, credit cards, atm cards, parking tickets, etc., unless you want them wiped clean.
 
Yes, definitely, the MRI will NOT be on. If nothing else, those darn things are louder than a freaking cannon. Why they make ANY noise is beyond me, why they make those loud noises is incomprehensible to me. Obviously, there's a reason.

Mark, did you use a fluid head? Any special precautions you took?

Stephen
 
With the machine off, the only thing I was concerned about was messing up their fancy big doughnut, which brings up another question, is it the classic MRI or an open unit? With the open one, you'd have many more options about how to set up. If given the choice, I'd choose the open flavor.

Oh, to answer your question, this was pre-RED shooting, so no to the fluid head as it was stills. However, I wouldn't have an issue using a fluid head in the room.
 
An MRI has inside a very strong static magnetic field between the poles. This is needed to align so-called magnetic moments within the human body. In addition an MRI-magnet generates a RF-field oscillating the magnetic moments in resonance. Outside the magnet there is a stray field, but it is not dangerous. To give an idea, when one holds a permanent magnet in hands, the field is locally much stronger than the stray field of an MRI. The RF field of the magnet is neither a concern. MRI is not comparable to X-ray imaging.

Technically the aluminium cover of the camera shields RF-field, but the static stray field affects all magnetic objects. That's why the magnetic stripe of a credit card, parking ticket etc. may get magnetized and the information in it blurred. And yes, there is a force between the MRI magnet and magnetic objects, such as steel parts. When the distance becomes smaller, the force increases quickly. This can be rather surprising when one gets too close, see

http://www.nytimes.com/2005/08/19/health/19magnet.html?_r=1&pagewanted=all.

Notice also, if you are using RedRaid, the magnetic field could mix up the HD. Although the aluminium cover does not shield from a static magnetic field, electronics in general is not sensitive to it.

Summing up, the main risk is the magnetic forces between the magnet and ferromagnetic objects (made of iron, steel, nickel, cobalt) or between the MRI and permamemt magnets. Have no idea whether there are ferromagnetic parts within Red One or Epic.
 
Mark Phelan said:
I would suspect the machine was off when these were taken. Otherwise, no technician will let you near the machine when it is on. I've shot MRIs both on and off. When on, you "might" be able to be let inside the room, but probably not. Shooting through the door works or through the window, but sometimes the window has a screen mesh on it, so that presents issues. They are going to be much more concerned with the safety of the MRI than about your silly little camera and lighting equipment.

Personal story time. Shot an MRI back in 1988. It was an out-of-town trip and when I got back to town, I was trying to exit the parking lot at the airport. The machine wouldn't read my ticket for some reason. The gal in the ticket booth asked if I'd been near any magnets, then it dawned on me. Take EVERYTHING out of your pockets, credit cards, atm cards, parking tickets, etc., unless you want them wiped clean.
Click to expand...

As far as I know, MRI machines are never really "off" except for maintainence. I'd say to talk with an MRI technician before you plan any shots.
 
Exactly. My client was an MRI company, so we had access to machines that were being serviced.
 
I have shot several times a MRI scene in hospitals both in the UK, Eire and Dubai and have never ever been allowed into the room even,you must stay outside the Faraday cage.
Even when the MRI machine is off (it is never truly off)
The only time they would allow us in the room with equipment was if the machine was being serviced....But was told that was never going to happen either :)
 
Well, I hate all of this contradictory advice.

Some say it's no problem. Some say it won't work.

Access will not be a problem. . . we have an in with a doc, but I sure don't want to blow up my One, either.

Stephen
 
Actually, everyone is saying pretty much the same thing, you can't go inside the room with equipment when the machine is on, which is pretty much all the time except for when it's being worked on. BTW, they can't just simply turn it off either. From what I remember, there's liquid nitrogen used to cool the magnet and it takes them a long time to get things off and back on.

The magnet can yank your equipment into itself with tremendous force. See here: http://www.simplyphysics.com/flying_objects.html

Another point of discussion as long as we're portending doom and gloom, old tattoos might be very painful if the ink used contained traces of metal, or any other metal objects in your body from say, surgery or shrapnel.

But you should be fine. To be safe, use a telephoto from the building across the street. :wink5:
 
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