photo and video welding

[Sberry]

Who has done closeup work with welding? We tried a couple filter plates but there is huge improvements needed, anyone done this or know someone who has?

[whateg0]

Cary, Those are neat photos. They don't show anything really useful, but they'd be cool for a website. I guess the real reason I'm posting is to subscribe, cuz there've been a few times where I'd have liked to taken some pics of some welding.

Dave

[Sberry]

Yes, they were just messing around trying to be artsy.

[84ZMike]

My neighbor is a retired owner of a pro photo shop...I'll ask him as I know he did some at one point....
Mike

[Broccoli1]

Cary,

you are going to have one heck of a time:)

It doesn't matter what filter/lens you use because the Arc is just too bright and the camera has to Expose for either the Bright area or the Dark area:

If you expose for the bright ARC then the dark goes way dark

If you expose for the Dark area then the Bright area is way too bright.


Pretty much like trying photograph the Sun:)

Ideally what you need is a Center Weighted Filter. This where the dark area of the Filter is in the Center only and fades away to clear towards the edges but they don't make one dark enough for your needs.

The other option is to blast the surrounding area with light to even out the exposure but dat's gonna take a lotta light:)

If you have a couple of 1000w halogen work lights get as many as you can and use them to light up the Weldor and work area.

[whateg0]

How hard to you think it would be to take a photo with a fast shutter time and then another with a long shutter time and Photoshop them to get the desired effect?

Dave

[Broccoli1]

How hard to you think it would be to take a photo with a fast shutter time and then another with a long shutter time and Photoshop them to get the desired effect?

Dave

I assume the fast shutter speed is for the Arc- no problem

Slow shutter speed is to allow more of the ambient light BUT then you'll most likely get movement of the Weldor.

Your idea is done all the time with Architectural Photos- say a nice shot of a Fancy board room with windows or several types of lighting in the room.

First exposure is done with accents lights on- then urn lights off take another pic, sometime even wait until sunset and take the first exposure of the sunset through the windows. Wait some more until dark and then shoot another exposure of the lights on in the room.

All of this done on the same piece of film. Just keep shooting without advancing the film, or with 4x5 or 8x10 sheet film just leaving the film in.

[whateg0]

I didn't mean realllllly slow. I know with my 4 year old Nikon I have trouble taking photos of things like fireworks - even on the fireworks setting. Never had that with film. I kinda figured a digital 'double exposure' could be done somehow. I've just never done it. But it might help in the situation Cary suggested. Course, it'd be like a cut in a movie. Everybody has to be in the same place for it to look right.

Dave

[Broccoli1]

Fireworks-Film has more latitude than Digi:) even if you don't get the correct exposure in the camera you can save the shot in the darkroom when you print.

Digi has the benefit of knowing right away if you didn't get the exposure in the camera- so you just shoot it again.

Doing a double exposure with a person is tough- they tend to move:)

[txfireguy2003]

It's not so much the shutter speed as it is the f-stop (aperture setting). The smaller the aperture, the less light is allowed into the lense and onto the film. Again, the problem is that the arc it too bright and you can't get the aperture small enough to darken it without making everything else black, and vice versa.

[whateg0]

It's not so much the shutter speed as it is the f-stop (aperture setting). The smaller the aperture, the less light is allowed into the lense and onto the film. Again, the problem is that the arc it too bright and you can't get the aperture small enough to darken it without making everything else black, and vice versa.

Sorry, the shutter speed vs. aperture was my mistake. Nonetheless, it seems like a person could take a photo of the scene without an arc present to provide the surroundings, and the take a photo of the scene with an arc present to get the arc. Then the two photos could be merged. Isn't that possible?

Dave

[Rocky D]

I've seen a photo taken through a welding lens...prolly an 8, the trick is to use manual focus...if your using a digital, camera you should have wsiwyg also. Use a 4 x 5 lens to protect the camera.

[txfireguy2003]

Sorry, the shutter speed vs. aperture was my mistake. Nonetheless, it seems like a person could take a photo of the scene without an arc present to provide the surroundings, and the take a photo of the scene with an arc present to get the arc. Then the two photos could be merged. Isn't that possible?

Dave

I think it could be done. As a matter of fact, I'm pretty sure it could. One of the guys I work with was showing me some software he was using to rework some photos he'd taken. He does pro photography work on his days off from the FD and this family had commissioned him to take a family portrait, outdoors, with about 15 or some people, all wearing white shirts. The problem is that the light hits each one differently, so some of the shirts look great, while others look too dark and other look so bright they're washed out looking. I'm not exactly sure what he did, or what program it was, but he had two photos and merged them together to make one photo that looked pretty decent. If I remember, I'll ask him what program he was using.

[Broccoli1]

It's not so much the shutter speed as it is the f-stop (aperture setting). The smaller the aperture, the less light is allowed into the lense and onto the film. Again, the problem is that the arc it too bright and you can't get the aperture small enough to darken it without making everything else black, and vice versa.

Shutter speed and Aperture work together:)

Smaller f-stop + shutter speed = Correct exposure

Bigger f-stop + shutter speed = Correct exposure

f16 (more light through the lens) @ 1/250th shutter speed (shutter speed controls the amount of light coming in through the aperture by time)
or
f22 (less light) @ 1/125th but now we have allowed more time:)

Same exposure


Cary, it would be a bit easier to do it during daylight and let the Sun throw some light at the subject. Still have a problem filming the ARC but the overall exposure would be a little better balanced.

You can easily see how bright the ARC (and the problem) because in daylight the welding ARC is pretty much the brightest thing around.

[Broccoli1]

Sorry, the shutter speed vs. aperture was my mistake. Nonetheless, it seems like a person could take a photo of the scene without an arc present to provide the surroundings, and the take a photo of the scene with an arc present to get the arc. Then the two photos could be merged. Isn't that possible?

Dave

Sure- Car doods do it all the time.

Shoot a Background Plate and then drop the Car into the shot but you are talking about some serious time working the image in Post.

Dave, remember my Chop Saw shot with my boy?

I shot the saw by itself and then shot it again with him standing there so it looked like he was operating the saw- sparks and all:D

[Broccoli1]

Sorry, the shutter speed vs. aperture was my mistake.

Dave

Dave you had it correct- changing the aperture will change the Depth of Field

Shoot the 1st shot at say f8 and whatever shutter speed (fast) to get the exposure for the Arc.

Shoot the 2nd shot at f8 and then whatever shutter speed (slow) to get the exposure for the surrounding area.

[Broccoli1]

Here it is:D

[Rocky D]

So easy, a cave baby could do it! :D

[Sully2]

Who has done closeup work with welding? We tried a couple filter plates but there is huge improvements needed, anyone done this or know someone who has?

You need a center weighted neutral density filter(s). A light reading ( using a hand held light meter) of the ambient light..AND of the "spark" of the welding operation. By comparing the two, that tells you how many stops of filter you need to cut the center portion ( the sparc) down.

It looks like from the "rays of light" that are spurious in the pics..you may also need a polarizing filter.

If the difference in "stops" are too drastic..you will need BRIGHT lights to bring UP the light of the "background".

If you dont have a SLR ( digital or film) that you can set to fully manual...adjusting shutter speed / apeature based on the light readings and the "film" ISO...basically...your screwed!

[JimYo]

my daughter took this one with some sun light and the arc hidden a little by the vicegrip... nikon with no filter
Jim

[enlpck]

I'v had some success with a point-and-shoot digital using a gold filter in from of the lens, forcing the focus (setting for macro and positioning at the maximum distance for the macro setting) and using LOTS of extra light... several halogen heads, for example.

The camera I use picks exposure from the center of the frame, so I can either force the exposure to show the arc and pool (sort of), or the background, depending on if I aim dead on or a little off center.

No pics handy on this computer... I'll see if I can find some later.

[Sully2]

my daughter took this one with some sun light and the arc hidden a little by the vicegrip... nikon with no filter
Jim

Yepper! Sunlight brought up the ambient light..but of course the welding arc is still FAR over exposed

[Sberry]

I am familiar with the basics of photography, the ideal thing for us would be to do macro video of actual puddle. I was considering gold lenes also but didint have a large one around, might try an 8 in that.

[DrIQ]

As suggested setup several halogen lights to add to the ambient light.

For your filter use a light oxy filter lens as your primary and then cut a small round secondary filter shade 10 at a diameter to cover the actual arc and center it on the oxy filter. You will be able to see the weld puddle very well using this process.

The challange is getting the secondary filter the right diameter to just cover the arc.

The process worked well for the welding process training films that were made at the Hobart Institute 30 years ago.

[Sully2]

I am familiar with the basics of photography, the ideal thing for us would be to do macro video of actual puddle. I was considering gold lenes also but didint have a large one around, might try an 8 in that.

The welding DVD I have here shows that. The instant the arc is struck..the lights go totally dark...and thus the "proper exposure" is based on the arc light itself. Shows clearly.. As soon as the arc STOPS...the ambient lighting comes back on