Maximising The Source: understanding reflected light

Essential viewing for those wishing to learn about reflected light and the dedolight Lightstream system.
This presentation tells how photographer Taki Bibelas came to understand the value of reflected light early in his career, to then refine this into his own workflow. This is presentation is packed with information and real-world examples showing just what can be done with dedolight Lightstream.
Thanks to Taki Bibelas for this stunning presentation!
Taki Bibelas started as a fashion photographer in Paris, having worked for major magazines around the world. He has since worked in filmmaking as a director, editor, producer, DOP, videographer, across many areas, including: corporate video, brand awareness video, testimonials, advertisements, documentary.
More from Taki on Instagram @takibibelas
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[@flaviopresutti]

Really great demonstration, I love this lightstream system!

[@PenFriends]

It’s a wonderfully compact setup, but I still feel giant scrims give you much nicer quality of soft diffused light. But I could see this working in tighter working conditions

[@erikburmeister4241]

Люто плюсую! Спасибо за навык!

[@DynastyUK]

how do these reflector differ from a mirror, or mirror with diffusion gel attached?

[@boschulte]

I’m confused how the inverse square law relates to the constant exposure? I would think that he would lose a stop of light every time your distance doubles.

[@anaphael1538]

Hey its a bit roughly brushed over in the video. You can imagine it like this: a normal light fixture will have exactly this effect. You double the distance you will lose 2 stops. So when a person gets closer for example the brightness increases significantly. If you use reflected light, the lightsource is further away most of the time because for example have the light mounted on the floor shooting up into a mirror. So now you have the lightsource further away, because it travels from ground up into the mirror to the subject. so you added 1,5 meters for example of way that the light needs to travel. So the same movement from the person now happens further away from the light. so the change wont be so drastic. This effect is even more enhanced with the parallel beam attachment, i wont go into details here, but the attachment makes the lightsource behave like an even further away lightsource. For example it makes it feel like 5meters behind the actual light. Now you have 6.5 meters of the light traveling before it is at the point of here your previous light would be. If the person would walk from 2 meters to 0.5m to the mirror With the parallel beam attachment on the light they would gain under half a stop of light. Same scenario with a direct source where the mirror was would be 4 stops exposure increase. I hope that clears it up for you (google inverse square law with f stops than the whole thing becomes a lot clearer)

[@boschulte]

@el1538 makes sense... the rays are more parallel therefore they are not spreading. ingenious... the exposure will remain more steady. Thanks for taking the time to explain.

[@ottawamountainman]

The presenter “misspoke”. The exposure remains contant not because of the inverse square law but because the inverse square law does NOT apply here; it only applies to light that radiates freely away from a point source. It does not apply to “parallel” or collimated light, focused light or light that is otherwise modified with intensifying reflectors or blocked by grids (occlusion effect). That’s the entire premise of this system= inverse square law does not apply to this light source. To be clear… the magic here has to do with that amazing light source with the special lens on it - and not the reflectors used. If you don’t have that or similar light then this trick with these reflectors will not work.

[@VectorClassics]

Does the inverse square law not explain the reason the fall of is not the same is because of the distance of the source

[@ottawamountainman]

​@@VectorClassics the light from a "normal" source like a light bulb, or a strobe, or a COB will radiate away from the source as an ever expanding sphere. The further you are from this source the less light density there will be from your perspective. If you double your distance from this source then you will perceive 1/4 the intensity of light from where you stand. That's the inverse square law. It is because the light is an expanding sphere as you move away from its source. But with tools like a PERFECT mirrored parabola and with a light source placed in the "focusing position", or with "special" lenses (like in this video) you can *collimate* the light rays to project PARALLEL to each other as the rays move away from the source; and not in an expanding radial way.... This is what is being used in this video. Again, it should be emphasized, that the magic in this video is because of the fancy light they are using and NOT the $$$$ reflectors (the tittle is a little ... deceiving). Note: with "normal light" if you cast a shadow on the wall with your hand; the shadow will be crisp close to the wall and become larger and fuzzy as you move your hand away from the wall and towards the light source. This does not occur with perfectly collimated light; shadows are crisp irrespective of distance...there is NO fall off .... the rays are parallel. You can APPROXIMATE this effect by using a normal radial light source placed VERY far away. From your perspective those rays will seem parallel; that's the case for the sun. So, you can reproduce this video by using sunlight and reflectors. You can try this with the aluminized side of insulation foam boards you get from Home Depot; you can easily cut them to the size you want. As for using GRIDS over your lights or strobes... well that's a more complicated discussion and has to do with a principal called OCCLUSION; and this principle can also help you prevent the light fall off you would expect from the inverse square law....