Jump to content


Photo

How Are These Pervasive Lens Flares Created?


  • Please log in to reply
15 replies to this topic

#1 Peter Ellner

Peter Ellner
  • Basic Members
  • PipPip
  • 30 posts
  • Student
  • California

Posted 04 October 2011 - 10:08 PM

In professional work, I often see a type of beautiful rainbow-like lens flare that I never see in less professional work and have unfortunately never been able to create on my own with the tools I have. I would love to know what these types of lens flares are called, and how to purposely and artistically create them.

The ones I'm talking about are different than simply reflected images of a light source, veiling glare, or light in the shape of the camera's aperture, but another type of lens flare in addition to those. It often looks like a sideways rainbow, but striped rather than continuous.

Here are a few examples if you don't know what I mean:
www.flickr.com/photos/12557378@N06/6171005435/in/photostream/
www.flickr.com/photos/12557378@N06/6171549378/
www.flickr.com/photos/12557378@N06/6171005535/in/photostream/

Also, in some films, but not all, light sources will have a circular halo of light around them as in this shot from Blade Runner: http://www.flickr.co...in/photostream/
This is distinct from the diffraction sunbursts due to a small aperture, so I was wondering what this effect is called and what causes it as I don't see it in every film.

Thanks so much guys!
  • 0

#2 Peter Ellner

Peter Ellner
  • Basic Members
  • PipPip
  • 30 posts
  • Student
  • California

Posted 04 October 2011 - 10:26 PM

I'm sorry, none of those links seem to work unless you're signed in to Flickr.

Try these:

Lens Flare Examples:
http://www.flickr.co...N07/6213305128/
http://www.flickr.co...N07/6213305050/
http://www.flickr.co...N07/6212790413/

Blade Runner Example:
http://www.flickr.co...N07/6213304922/
  • 0

#3 steve waschka

steve waschka
  • Basic Members
  • PipPipPip
  • 204 posts
  • Industry Rep
  • Indian Harbour Beach, FL

Posted 05 October 2011 - 07:58 PM

i believe blade runner was shot with panavision anamorphics. im assuming the rest of the places you have seen the flare are probably not shot with the same lenses or from the same period of DI technology as blade runner. using that as a base, id guess the flare you see could have been created by diffraction glass.
  • 0

#4 David Mullen ASC

David Mullen ASC
  • Sustaining Members
  • 19759 posts
  • Cinematographer
  • Los Angeles

Posted 05 October 2011 - 08:42 PM

That efx shot from "Blade Runner" was shot in 65mm spherical, you can tell because the red ring would have been oval, not round, if it had been shot in 35mm anamorphic.

The red ring comes from using an older lens with an uncoated element, same goes for when an older anamorphic lenses has such an element -- in fact, the ring is round even in anamorphic, it's just that the circle is stretched into a horizontal oval when the image is stretched by 2X horizontally when unsqueezing the image.

See this anamorphic 35mm shot from "Logan's Run" before and after I unsqueezed it:

Posted Image

Posted Image
  • 0

#5 Stuart Brereton

Stuart Brereton
  • Basic Members
  • PipPipPipPip
  • 3065 posts
  • Cinematographer
  • Los Angeles

Posted 05 October 2011 - 11:31 PM

from the same period of DI technology as blade runner.


Blade Runner was released in 1982. There was no DI technology at that time. The first Hollywood film to go through a DI was 'O Brother, where art thou?', some 18 years later.....
  • 0

#6 steve waschka

steve waschka
  • Basic Members
  • PipPipPip
  • 204 posts
  • Industry Rep
  • Indian Harbour Beach, FL

Posted 06 October 2011 - 11:46 AM

Blade Runner was released in 1982. There was no DI technology at that time. The first Hollywood film to go through a DI was 'O Brother, where art thou?', some 18 years later.....


exactly.


the way those rainbow rings are kind of broken and not continuous circles (not the blade runner pic... that one looks more continuous), reminds me of some of the diffraction filters. or a di effect. the three filckr pics have very similar flare. the blade runner appears different. at least to me. since it wouldnt have been an add-in affect.....

Edited by steve waschka, 06 October 2011 - 11:49 AM.

  • 0

#7 David Mullen ASC

David Mullen ASC
  • Sustaining Members
  • 19759 posts
  • Cinematographer
  • Los Angeles

Posted 06 October 2011 - 12:08 PM

It's just an artifact of the lens technology of the day, not a trick. You can still get those rainbow flares using the old C-Series Panavision anamorphic lenses today.
  • 0

#8 steve waschka

steve waschka
  • Basic Members
  • PipPipPip
  • 204 posts
  • Industry Rep
  • Indian Harbour Beach, FL

Posted 06 October 2011 - 12:11 PM

i missed seven days. gonna have to bluray now.
  • 0

#9 Stuart Brereton

Stuart Brereton
  • Basic Members
  • PipPipPipPip
  • 3065 posts
  • Cinematographer
  • Los Angeles

Posted 06 October 2011 - 09:33 PM

exactly.


Huh?
  • 0

#10 Peter Ellner

Peter Ellner
  • Basic Members
  • PipPip
  • 30 posts
  • Student
  • California

Posted 06 October 2011 - 11:01 PM

That efx shot from "Blade Runner" was shot in 65mm spherical, you can tell because the red ring would have been oval, not round, if it had been shot in 35mm anamorphic.

The red ring comes from using an older lens with an uncoated element, same goes for when an older anamorphic lenses has such an element -- in fact, the ring is round even in anamorphic, it's just that the circle is stretched into a horizontal oval when the image is stretched by 2X horizontally when unsqueezing the image.


But what actually causes that ring in the first place? I can see how having uncoated lenses can contribute to its existence, but why is it a ring of light rather than just a diffused glow?

It's interesting how the anamorphic lens actually projects a circular, rather than elliptical, ring on the film. Why is that, doesn't the anamorphic lens "squish" everything?
  • 0

#11 Peter Ellner

Peter Ellner
  • Basic Members
  • PipPip
  • 30 posts
  • Student
  • California

Posted 07 October 2011 - 12:12 AM

Also, I was gonna start a new topic for a couple of anamorphic lens questions, but maybe I'll just post them here and see if anyone knows:

Anamorphic lens flares are characteristically blue...is there any known reason for this?

Is it true to say that anamorphic lenses work by basically being hyper-astigmatic, in the sense that their horizontal focal length is shorter than their vertical focal length? If this is true, than how is it possible for an anamorphic lens to create an image that's in focus, since having a different focal length in each meridian of the lens would mean horizontal and vertical features would come to a focus at different points?

Thanks for the insights!
  • 0

#12 Peter Ellner

Peter Ellner
  • Basic Members
  • PipPip
  • 30 posts
  • Student
  • California

Posted 07 October 2011 - 12:23 AM

Edit:

I think I just figured out the first one, it's due to the anti-reflection coatings on the lens, isn't it? But then if the light sources look blueish, why don't anamorphic lenses make everything look blueish?

Edited by Peter Ellner, 07 October 2011 - 12:23 AM.

  • 0

#13 steve waschka

steve waschka
  • Basic Members
  • PipPipPip
  • 204 posts
  • Industry Rep
  • Indian Harbour Beach, FL

Posted 07 October 2011 - 02:32 PM

Huh?


sorry... my original comment was meant to infer that the photos were probably not shot or handled in the same way what-so-ever. i dont use much di effect as i almost always overcook with the stuff, i have never shot with panavision, but its pretty popular gear and david mullen would know so ill go with his response, and i dont think peter meant to include the blade runner shot in the same comparison anyways. so i wasnt a careful reader. but i have seen some mild diffraction filters that i thought he might be able to play with and get a similar effect.

Edited by steve waschka, 07 October 2011 - 02:33 PM.

  • 0

#14 Phil Rhodes

Phil Rhodes
  • Sustaining Members
  • 11938 posts
  • Other

Posted 07 October 2011 - 05:45 PM

About it being blue.

Lenses have "thin film coatings", which means that the coating is somewhere near a multiple of the wavelength of the light. This causes it to exhibit dichroism, that is, it will reflect some wavelengths and transmit others, just like oil on water. Thus the colour can be affected by the angle of incidence, because at a shallow angle the beam of light passes through a greater thickness of coating than it does at right angles to the surface.

The colour and geometry of lens flares is created by a combination of the lens elements, their coatings, other reflective objects inside the lens barrel, and the physical layout of all these components.

The fact that the flare is blue implies that the red and green light is simply going somewhere else - being reflected, as opposed to transmitted, perhaps. The inside of the lens barrel is usually painted matt black to minimise all these effects.

P
  • 0

#15 Harry Capota

Harry Capota
  • Basic Members
  • PipPip
  • 10 posts
  • Cinematographer

Posted 26 November 2011 - 06:11 PM

I'm sorry, none of those links seem to work unless you're signed in to Flickr.

Try these:

Lens Flare Examples:
http://www.flickr.co...N07/6213305128/
http://www.flickr.co...N07/6213305050/
http://www.flickr.co...N07/6212790413/

Blade Runner Example:
http://www.flickr.co...N07/6213304922/



I own a couple of still lenses which have a similar flare effect

check out:

Attached Images

  • viv.jpg

  • 0

#16 David Mullen ASC

David Mullen ASC
  • Sustaining Members
  • 19759 posts
  • Cinematographer
  • Los Angeles

Posted 26 November 2011 - 06:16 PM

Not all the elements in a lens are the same size, plus as they get reflected on the surface of other elements, which all have curved surfaces, the reflection may be reduced or enlarged in size, plus the elements that are farther away will produce a smaller reflection in another element that is spaced apart, all this to explain why rings and other circles appear, not just a haze around a light on an uncoated element.
  • 0


CineLab

Ritter Battery

Rig Wheels Passport

Visual Products

Opal

Tai Audio

Technodolly

Abel Cine

CineTape

FJS International, LLC

Wooden Camera

rebotnix Technologies

Gamma Ray Digital Inc

Glidecam

Willys Widgets

The Slider

Media Blackout - Custom Cables and AKS

Paralinx LLC

Broadcast Solutions Inc

Metropolis Post

Aerial Filmworks

rebotnix Technologies

Tai Audio

Broadcast Solutions Inc

Opal

Abel Cine

Metropolis Post

Technodolly

Rig Wheels Passport

The Slider

Aerial Filmworks

FJS International, LLC

Willys Widgets

Visual Products

Wooden Camera

Media Blackout - Custom Cables and AKS

Gamma Ray Digital Inc

CineLab

CineTape

Paralinx LLC

Glidecam

Ritter Battery