safety glasses/goggles?

[laserlackey]

Thanks laserlackey. One question: have you tested them? (not saying if youve actually looked directly at a laser beam obviously ).

Well, I haven't blasted myself in the face just for the sake of testing them however, I do know that it made alignment WAY easier. In my specific application, I was forced to align much closer to full power than is ideal. It made the task doable and safe. The goggles I bought were rated OD7 in my chosen wavelength, and I couldn't see any scattered light with them on (I had a 6+W beam over 4 sq. cm. during full-power alignment). Without them on, I wouldn't have wanted to do it for fear of going blind off the scatter alone.

That being said, I caution you to buy the highest rated protection factor you can possibly afford. Some would probably say that OD7 is overkill, but I always try to err on the safe side. Even with OD7, I could still see the beam profile on my projection surface for alignment purposes. It showed up as a faint yellow-ish glow (which I'm told is actually the heat from the beam, not the light directly, which is a little disturbing to think about).

[White-Light]

Those damaged cameras on LPF were from high power lasers focused to burn. Not a beam thats focused for a 30 foot shot. And they were small lines, not wiped CCDs.

Plenty of evidence on Youtube in fairness, even from some distance:



Total sensor wipe (near end):



If you're at home, best simply to tripod and BAM the camera (or keep it out of the beams entirely).

[TechJunkie]

Hey White. You're not following the conversation. We are talking about the view of the beam from the projector side, not audiences. Most of the cameras on LPF are on the burning side of the beam, and way lower power than those projectors. Of course if you hit a camera with a 20W+ projector beam things are going to go wrong.

Once again I know someone who built this, but used cardboard as the enclosure instead of the welding goggles. It works, and you can build one for under $30. If it lasts a month you got your monies worth. For all the money you guys spend on equipment you're getting way to literal over a $30 project that could easily last for years. Its a good idea and all you guys do is keep arguing that the laser can burn the camera. Who cares, used phones are $15, make another. You can buy over 10 phones for the price of one set of multi-wavelength goggles. Try making one, you might like it, my friend did, and it made great videos. Its been on my to-do list for a long time, I just never needed them till I got into the projector field. My OEM ARGs were all I needed with the pointers.

Thanks Doc. Always appreciate your advice.

[White-Light]

Ah ok Sorry Tech. So what we're talking therefore is brightness damage rather than a direct hit. I must admit, I've never seen pure brightness damage before. I've actually seen more CCD flare from LED's than from shots taken from outside of a laser beam and I've never seen anything from shots taken from directly behind it. I guess some CCD's are a lot more sensitive now.

[buffo]

The threshold for camera damage is far lower than 500 mw!

I have an old Fuji Fine-pix 3.1 Megapixel camera that has a bunch of burn spots on the CCD from taking pictures of SCANNED effects from a 100 mw laser.

Some sensors are more susceptible to damage than others. And as a rule of thumb, higher resolution cameras are at greater risk.

Adam

[TechJunkie]

Hey guys sorry if I'm a little argumentative. I've always been this way, but try hard not to be.

If I make one of these I'll post a DIY review if it works good.

[swamidog]

i've never had a problem taking pictures of projected images or filming my shows.

So wait i can damage my camera not only when beam hits it but also when i record a projection on wall?

[The_Doctor]

So wait i can damage my camera not only when beam hits it but also when i record a projection on wall?

Maybe. How long is a piece of string? The important point being that string has length. Just because the quantity isn't easily specified does not mean that the basic quality of length is not there, and it may be long.

There is a reason that a Class 4 laser is meant to be accompanied by a warning that eyes and skin should be protected even from diffuse reflections. So it stands to reason that a sensitive camera can't be assumed to be safe either.

The coherence of the light means that even a diffuse reflection may contain clusters of strongly coherent light, and high energy density, even after a diffuse reflection. To prove this, shine a fixed beam at a white painted wall, then look closely at the far wall, on the other side of the darkened room. Plenty of bright hotspots all over it...

[White-Light]

+ 1.

Also the simple answer is don't use expensive cameras or sensitive cameras unless you're prepared to take the damage and financial loss.

I have a Casio Z80 compact. It's Ok for video, pretty poor for laser stills (ok normal photography). There are better cameras around for laser photography. What it is though is relatively cheap and very laser resilient. It's taken exposure at approx. 550 MPE without a single pixel loss!

[Eidetic]

Anyone thinking about using a cell phone attached to a welder's goggle body should hold their phone's screen 2" in front of their eyes, and tell us all how easy it is to see the images on it for more than 30 seconds. I'd do it, but at 57 my eyes can't focus anywhere near that close anymore and no eyeglasses will do the job. Then there's field of view differences for each eye. A truly bad idea.