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  1. #1
    hec
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    photographing arc welding

    hello,

    has someone here photographed arc welding? I have searched without success regarding a recommended exposure. BTW, I will be using Ilford fp4.

    Because I look forward to having long spark lines on the photograph, I would guess that in order to accomplish that it would be required a shutter speed between 1/4 and 1/30.

    Thanks for your advice...

  2. #2
    markbarendt's Avatar
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    I think you are on the right track.

    You may want to bracket and I'd suggest longer exposures yet; longer exposures mean not just longer trails but more trails.

    The welding and sparks are point sources, like light bulbs. If you expose for a light bulbs burning filament everything else will be quite dark.

    With the longer exposures you may want to use a flash to freeze the person welding.

    So in practical terms what I'm suggesting is to set the camera for around 2-3 stops underexposed from ambient, use a shutter speed closer to 5-10 seconds, use flash to get the person properly exposed.
    Mark Barendt, Ignacio, CO

    "We do not see things the way they are. We see things the way we are." Anaïs Nin

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    Be careful not to look at the arc, it's extremely bright and you may get 'arc eye' which is very nasty. Once or twice I struck the arc just before I could get the mask to my eye and the brightness was so intense I couldn't see anything but pure white for some seconds (I used to work as a toolmaker). I'd be hesitant to look at the arc through a camera lens, maybe set up on a tripod and use a welding mask like the welder.

    http://en.wikipedia.org/wiki/Arc_eye

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    markbarendt's Avatar
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    Quote Originally Posted by perkeleellinen View Post
    Be careful not to look at the arc, it's extremely bright and you may get 'arc eye' which is very nasty. Once or twice I struck the arc just before I could get the mask to my eye and the brightness was so intense I couldn't see anything but pure white for some seconds (I used to work as a toolmaker). I'd be hesitant to look at the arc through a camera lens, maybe set up on a tripod and use a welding mask like the welder.

    http://en.wikipedia.org/wiki/Arc_eye
    Ditto!
    Mark Barendt, Ignacio, CO

    "We do not see things the way they are. We see things the way we are." Anaïs Nin

  5. #5
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    Looking at the people and things on your website one would guess that these will be very close to the fire. I would encourage you to take many shots bracketing your exposure by many stops. You will have a wide range of light, way beyond the capability of the film, so much of your success will be by chance. The more varied shots the better your chances.

    This sounds like a very interesting subject especially at the close range you use. I hope you will share your pictures with us, either here or on your website. Please let us know how the project goes.

    John Powers

  6. #6
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    I don't have any to show, as they're Ektachrome, but I have gotten some good arc welding photos. I used a welding face glass over the lens. This protects the lens and cuts the brightness and UV for both the camera and your eyes.
    Mind what perkeleellinen says. Looking at the arc without protection can permantly damage the retina worst case, and will cause severe pain due to 'sunburn' of the eyes.
    Using flash to fill in the scene is a good thing to try. If the subject is well lit, this may not be necessary. 1/4 sec. has worked for me, but you may want to try longer. Too long and there are too many streaks and the scene becomes confusing.
    Bruce

    Moma don't take my Kodachrome away!
    Oops, Kodak just did!


    BruceCSdunekPhotography.zenfolio.com

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    Quote Originally Posted by perkeleellinen View Post
    Be careful not to look at the arc, it's extremely bright and you may get 'arc eye' which is very nasty. Once or twice I struck the arc just before I could get the mask to my eye and the brightness was so intense I couldn't see anything but pure white for some seconds (I used to work as a toolmaker). I'd be hesitant to look at the arc through a camera lens, maybe set up on a tripod and use a welding mask like the welder.

    http://en.wikipedia.org/wiki/Arc_eye
    +1.

    I would add that arc welding produces a huge amount of UV light. Welders get lots of sunburns on their heads and hands (until they learn to cover up). You might want to use a UV filter, and you surely don't want to look at the arc when it's active, so tripod only and no looking through the lens. Wear UV safety glasses, look at the welder's face (mask) instead of the workpiece, and use lots of SPF-50 sunblock (a tee-shirt is good for about SPF-8 or less, and less if it's wet).
    Last edited by Bruce Watson; 01-06-2010 at 12:54 PM. Click to view previous post history.
    Bruce Watson
    AchromaticArts.com

  8. #8
    hec
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    thank you for your comments.

    I would be hesitant to use exposures longer than 1 sec. because I expect to get a sharp texture of the welder's mask and in my experience people hardly hold still for longer than 1/15, once I get into 1/8 I start to see a faint blur at the print. But I will give it a try to see it for myself.

    Regarding ambient light, the place is a long & tall warehouse with huge doors at both ends. So I have the option of putting a wall or daylight behind the welder, although I'd prefer a wall far behind to get better contrast on the sparks.

    I will be doing the photographs next Friday morning, a good friend has a workshop and has given me access. I will let you know how it turns out (and post a photo).

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    No welding, but if this picture I made is anything to go by in terms of what you might expect with arc welding, the following data may be of use (tripod used):

    Exposure
    F4, 1/10 sec.

    70-200mm / F2.8 lens used set at 200 mm.



    Marco
    My website

    "The nineteenth century began by believing that what was reasonable was true, and it wound up by believing that what it saw a photograph of, was true." - William M. Ivins Jr.

    "I don't know, maybe we should disinvent color, and we could just shoot Black & White." - David Burnett in 1978

    "Analog is chemistry + physics, digital is physics + math, which ones did you like most?"

  10. #10
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    I am looking at a Kodachrome of my dad welding, taken in the 50s. AFAIK, nothing special was done to adjust things by using filters or special exposures. The sparks are trails just as in Marco's photo and the arc shows surprising detail.

    I think what might confound us all is the fact that the arc appears bright to us, but all color films and some B&W films have UV protective layers. So this makes the exposure appear nearly correct. If it is not, then a UV filter would help.

    PE

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