How is this done? Seems like some kind of laser-effect

Discussion in 'Beyond the Basics' started by Pieter Van Goethem, Nov 3, 2018.

  1. Pieter Van Goethem

    Pieter Van Goethem TPF Noob!

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    Hi!


    I can't wrap my head around this shoot...

    Full shoot is here...
    Tomorrowland by Chuando & Frey for D'SCENE Magazine Visual Reality Issue

    At first sight, it looks like it is a long exposure laser...But how can it be that close to the eyes? And if it was a long exposure laser, how come it was even used during daylight?

    does anyone has an idea?

    Thanks!


     
  2. TCampbell

    TCampbell Been spending a lot of time on here!

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    It looks like a 523nm (green) laser.

    But here's the thing... they NEED to be weak lasers. In the old classification system, this was Class IIIa or below (e.g. IIa, II, I, etc.) Anything IIIb or above is considered dangerous.

    Any laser can be dangerous ... it depends on the laser's output power and duration of exposure. There's a notion of the human "blink reflex" where you'll close your eyes or turn away in response to bright light ... generally within 1/4 of a second. If the laser is weak enough that it can't do damage in that amount of time, then it's regarded as "safe" (it's not REALLY safe unless you understand the conditions and minimize exposure).

    Stronger lasers can cause damage (including lasting damage) much faster ... 1/100th sec... 1/1000ths sec. etc. where the blink-reflex is unlikely to save the eyes.

    Damage is a bit like a sunburn in that it can be a few hours (up to 48 hours) before you realize there is a problem.

    See: Laser safety - Wikipedia

    I should warn you that there have been numerous tests done with cheap lasers to check the output power ... only to find that the output power isn't what the customer expected (results were all over the place ... including much too strong.) Also lasers put out a "harmonic" frequency at double the wavelength (so this ends up in the infrared spectrum and it CAN damage eyes but isn't actually visible.) A quality laser will filter the harmonic.
     

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