Page 3 of 3 FirstFirst 123
Results 21 to 27 of 27

Thread: Question About Filming High Powered Laser Safely

  1. #21
    Join Date
    Nov 2009
    Location
    Maryland
    Posts
    320

    Default

    Great idea... if these work well for lasers this would be a fabulous camera to have in the shop. Or media room is not small, but putting a high powered laser even 20 feet from a $2K camera gives me the willies. I have ordered one and fingers crossed that it works!

    This won't really solve the larger project issue because we are talking about much bigger cameras there, but for shop use a little sacrifice camera may be the way to go!

  2. #22
    mixedgas's Avatar
    mixedgas is offline Creaky Old Award Winning Bastard Technologist
    Infinitus Excellentia Ion Laser Dominatus
    Join Date
    May 2007
    Location
    A lab with some dripping water on the floor.
    Posts
    9,890

    Default

    Post deleted as I just realized I had a sellable product that will protect video cameras as well as video projectors. X-Laser has been informed of the electrical concept.... The camera or projector does not have to co-operate, camera motion can be random, no polarizer, no software upgrade needed, and works with existing projectors. It has one tiny vulnerability, but that can be cured by choosing the frames used in the effects.

    Steve
    Last edited by mixedgas; 07-09-2014 at 09:28.
    Qui habet Christos, habet Vitam!
    I should have rented the space under my name for advertising.
    When I still could have...

  3. #23
    Join Date
    Nov 2007
    Location
    SoCal / San Salvador / NY
    Posts
    4,018

    Lightbulb

    Quote Originally Posted by X-Laser View Post
    ...initial idea was to add a neutral density filter to the front of the camera and boost the sensitivity to try and get back some of the brightness. The issue there is that the colors seem to desaturate and just don't look right.
    ..Also, that would likely dampen the colors of the rest of what was desired to be filmed in the scene, amirite? I have had good results trying pretty-much the same, though I usually put a 90% R mirror over the lens, and use a 'slow shutter', and the colors come out "good enough" for Client demos, etc.. But, clearly, this is a movie / video, etc, so I'm sure 'expectations are higher', so... Couple wakky ideas:

    a) Try shooting thru 'security mirror'? Something that's not as much a 'neutral-density' filter, as it is straight-up reflective, and that will certainly attenuate-power quite a bit.. 'Enough'? Dunno, but.. worth a try? And of course, you'll have to consider 'where that is reflecting the beams, back'.. Sure, for 'safety-sake', yada yada, but... also, they would likely not be keen with, ie: beams reflecting back into the scene / set / shot, etc.. So, that led me to the next krazy-idea..

    b) What about trying a 'reverse Pepper's ghost' / Schüfftan-process-type set-up?.. In other words, perhaps try not 'filming the scene', but a reflection of it-all.... I imagine rigging-up either a direct, first-surface mir, at / on the Lens-hood (..thereby freeing the cammy / jib to move, as freely as-needed..) or, a 'periscope' / pepper's ghost-type arrangement...

    ..The 'thought' is, it might allow for the scene to look like it's being filmed, 'head-on', but.. in reality, any 'straight-into-lens-view' beams that might reflect off the mir, might end-up coming-in at 'less-dangerous' angles that, ie: could end-up terminating on the hood / frame, etc, vs - for sure - pegging the cammy 'right in the eye' with straight-on shots... Worth a test-rig / shot?


    ..Thinking, too, that even-if you, ie: needed a *huge* mir (or two...) to achieve this, perhaps you could try and find someone, local, selling one / two of those 'giant old-skool 52" projection-tv's.. they're a *great source* of a - really, really big - and usually very-high-quali first-surface mir.. Very-likely, 'good enough', for at least this one scene.. I mean, assuming (cuz of the lasers.. this is a 'mostly-dark scene', where perhaps detail-lighting is not so critical-critical, and the shot can 'allow for a little sin' of any minor mirror-aberrations, etc..

    ..Just a wakky thought 'er two.. Hope it helps..
    j
    ....and armed only with his trusty 21 Zorgawatt KTiOPO4...

  4. #24
    Join Date
    Nov 2009
    Location
    Maryland
    Posts
    320

    Default

    Thanks Jon, also really good ideas!

    I might try the Pepper's Ghost. That's neat.

  5. #25
    mixedgas's Avatar
    mixedgas is offline Creaky Old Award Winning Bastard Technologist
    Infinitus Excellentia Ion Laser Dominatus
    Join Date
    May 2007
    Location
    A lab with some dripping water on the floor.
    Posts
    9,890

    Default

    If your going to do Pepper's Ghost with a high end camera you need a thin, coated, "Pellicle" beamsplitter, otherwise you get Fresnel's annoying Ghosts from the rear surface of a normal glass beamsplitter.

    Steve
    Qui habet Christos, habet Vitam!
    I should have rented the space under my name for advertising.
    When I still could have...

  6. #26
    Join Date
    Dec 2010
    Location
    DC/VA metro area, USA
    Posts
    554

    Default

    What about what they did for anti-laser protection for tank optics... put a delicate mirror at the focal point of a lens system in the optical path; if a high- energy burst enters the objective, it vaporized the mirror and protects whatever's behind it.

  7. #27
    Join Date
    Nov 2007
    Location
    SoCal / San Salvador / NY
    Posts
    4,018

    Lightbulb

    Quote Originally Posted by tribble View Post
    ...put a delicate mirror at the focal point of a lens system in the optical path...
    ..Good 'out of the box' thinking, but.. the 'issue' with any of the suggestions in this thread, that involve stuff inside the cam / 'on the CCD', etc, are likely not possible, because, what Film Production Co is going to allow modification of their Panaflex or Arri, etc, at the cost / risk of $$$,$$$-worth of camera-gear.. Likely, there's not even 'space' inside the bodies / lenses, for such mods.. So, it would (seem..) that the only workable solution(s) will have to be 'external' to the camera..

    ..Indeed, though, anyone / any Co that could come up with an 'in-camera incorporatable' something-something, that could act as a 'laser-hit shield', yet still allow for the full-gamut of color / light-density to pass.. would have themselves a boku-bux product..

    .02
    j
    ....and armed only with his trusty 21 Zorgawatt KTiOPO4...

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •