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Phil Hanna August 16th, 2011 04:31 PM

Shooting Arc Welding
 
Hello:
I have a video shoot next week at a welding shop in Ohio. The company does unique style of welding as we are going to put a piece together to demonstrate their capabilities. Has anyone shot video of welding? Is there a chance of blowing out the sensor on the EX-1 or the Canon EOS 7D? What precautions would you suggest?
Thanks,
Phil

Brian Drysdale August 16th, 2011 04:47 PM

Re: Shooting Arc Welding
 
I've shot welding on a number of occasions and never had any problems with the camera. However, I'd avoid looking at the welding arc itself directly with my eyes.

Dave Morrison August 16th, 2011 09:08 PM

Re: Shooting Arc Welding
 
Same here. I shot some heliarc(?) welders at work once and my EX1 had no problems.

Bill Ward August 17th, 2011 08:10 AM

Re: Shooting Arc Welding
 
And be prepared for some pretty extreme lighting contrasts, of course. I've had a lot of fun over the years adding high shutter speeds to the welding shoot to maximize the sparking and flaring.

Jim Michael August 17th, 2011 08:55 AM

Re: Shooting Arc Welding
 
Would one of those auto-darkening helmets work as a viewing portal for the camera?

Marcus Durham August 17th, 2011 08:59 AM

Re: Shooting Arc Welding
 
Quote:

Originally Posted by Bill Ward (Post 1675701)
And be prepared for some pretty extreme lighting contrasts, of course. I've had a lot of fun over the years adding high shutter speeds to the welding shoot to maximize the sparking and flaring.

Oh yes. I'd forgotten about this. Got some awesome footage on my Z1 in a welding factory. All the smoke really added to the atmosphere as well. Took lots of footage at different shutter speeds.

But as you say be warned about the brightness. You are going to have to compromise somewhere due to the extremes of light. You pretty much can't avoid overexposing the brightest parts of the arc.

And for god sakes watch your eyes. The camera is replaceable, your eyes are not! Keep well back and only view it through the camera.

I always shoot with a UV filter anyway but someone may be able to advise if there is any benefit in this for welding specifically.

Duncan Craig August 17th, 2011 02:29 PM

Re: Shooting Arc Welding
 
Firstly you should fit a clear filter on the camera lens something like a thin skylight. The Schneider UV 77mm slim fits under an EX1 lens hood. Metalwork and welding can and will send out shrapnel in every direction and depending on the type of welding it can still be very hot over quite long distances.

https://www.schneideroptics.com/ecom...D=992&IID=3918

A chap I know had a particle burnt into the front of his naked front element on a Digibeta camera, not a happy bunny.

It's very easy to forget that the front lens element is quite a bit closer to the action than you, so better safe than sorry.

But also wear safety glasses yourself, even if you already wear glasses, put clear protection glasses on top.
The client are bound to have spare pairs for you.

Duncan.

Bruce Watson August 18th, 2011 04:13 PM

Re: Shooting Arc Welding
 
First off, arc welding generates vast quantities of heat, light, and UV. Also fairly toxic smoke, and depending on what's being welded and how, sometimes a fair amount of shrapnel -- extremely hot and moving pretty fast.

I'm just sayin' that it's not a safe environment. You should protect yourself (heavy work clothes, no synthetic fabrics (plastics [nylon, polyesters, etc.] melt and make a small burn into a larger burn), long sleeves, long cuff leather gloves, safety glasses, safety helmet, etc.

DO NOT wear contact lenses near an arc welder. If you make a mistake and expose your eyes to the arc, you can flash the moisture between lens and eye, making surgical removal of the lens a necessity. Don't chance it.

The brightness of the arc is completely unnatural and can do a lot of bad things to your eyes. This is why so many welders retire at 40 and spend the rest of the lives in various stages of blindness. So DO NOT look at the arc, and do not expose your eyes to the arc even if you aren't looking directly at it. It's not worth the risk. If conditions permit, bring in a light stand and put a flag between your face and the arc so that you can only see the arc through the camera -- so there's no possibility you can make a mistake and look at the arc. That might be the smart play.

Same problem for the camera -- the camera isn't designed to handle a light source as bright as an arc, or with as much UV. I'd want to put an ND filter on the camera about at the same level as the glass in a welding helmet. I don't remember how many stops that is -- something like 14-18 stops? And a UV filter. Manually stop all the way down and open back up as required -- do it manually because the camera automation isn't even close to fast enough. And remember the inverse square law -- keep your distance and use the longer part of your focal length range.

Finally, cover all exposed skin with a physical blocker sunscreen (active ingredient of zine oxide or titanium oxide). A few minutes in the UV of an arc will give you a hell of a sunburn. And sunburned fingers are no fun at all.

Protect yourself, protect the camera, use some common sense, and you should do OK.

Brian Drysdale August 18th, 2011 05:12 PM

Re: Shooting Arc Welding
 
The ND that the welder uses allows them to look at the puddle of molten metal in the weld. This is of no use if you wish to film a scene involving welding because all you'd see would be the arc and nothing else. However, you can avoid directly filming the arc itself, by hiding it behind a bit of metal that's being fabricated, the welder's hand or the welding tool. You tend to get a lens flare if you film the arc.

Do wear appropriate clothing for the environment that you're working in, the company involved may have safety regulations regarding dress. Although, I'd differentiate between the gear that you'd wear if you were actaully doing the welding and filming welding at a safe distance. Do protect the front element with a filter if you're going to be within spatter distance and don't directly look at the arc itself.

Alister Chapman August 23rd, 2011 07:20 AM

Re: Shooting Arc Welding
 
Quote:

Originally Posted by Bruce Watson (Post 1676008)
DO NOT wear contact lenses near an arc welder. If you make a mistake and expose your eyes to the arc, you can flash the moisture between lens and eye, making surgical removal of the lens a necessity. Don't chance it.

This is one of those urban myths that is complete nonsense that has been medically disproved many, many times. It has been shown that contact lenses can in some cases be beneficial as they prevent airborne dust and irritants from contacting the cornea. The reported cases of contact lenses "welded" to cornea's were shown to be people that were arc welding without a proper welders mask and the UV light from the welding caused the cornea to break down, as would have happened to anyone's cornea without a suitable mask.

Normal sunscreen is of limited benefit as it rarely offers full UV-A protection and almost never any UV-C protection. UV-A and UV-C can cause skin cancer but neither cause sunburn or pain, that's UV-B. Sunscreen might stop you getting a tan but won't stop your skin from getting damaged. Proper protective clothing is the answer if you are close to the welding. Titanium Oxide is also a nasty carcinogen, Zinc Oxides does not provide any UV-C protection and only partial UV-A.

Phil Hanna August 27th, 2011 05:42 AM

Re: Shooting Arc Welding
 
Thanks to all who responded. The three-day shoot went beautifully. We got all types of welding, Mig, Tig, Laser and other milling shots around three plants. I used the EX-1 ND filters and the shots came out perfectly. What was neat was seeing the welder light up from total darkness since the ND filters were maxed on some shots.

Phil


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