[spam] [cml-glass] InfraRed Zooms
Evolve Films
On 29-Aug-18 6:22 PM, Mark Doering-Powell, ASC via Cml.News wrote:
I’ve been looking into sources for zoom lenses that have been coatedI have done a lot of work shooting IR. There is a fundamental issue with zoom lenses that in most cases make them unsuitable for use with infra red illumination. It comes back to the fact lenses are designed and optimized for visible wavelengths. The much longer wavelengths of near infra red, 0.75–1.4 µm means that the internal spacing between lens elements is not optimized for the wavelengths used with IR illumination. Given zoom lenses have many more elements than prime lenses this causes more issues, often halos, flares and generally soft images. So I generally stay clear of zoom lenses for this reason. There is also an issue caused by internal reflections from the interior of the lens barrels when IR light is reflected where visible light is not. Again causing flares and halos and central spots. I find that simpler the lens design the better the results. Often older prime lenses give best results, especially early Zeiss prime series or older (FD series) long (300mm plus) Canon prime still lenses seem to work quite well. (possibly because of simpler coatings or barrel design) It is also advisable to use IR band pass filters in front of the lens to block visible light and only allow the specific IR wavelengths you want to pass. There is a website that contains a lot of information re IR/UV shooting for stills and video. https://www.lifepixel.com/ Mark Lamble ACS DP Evolve Films Woodend Australia FYI I have no association with lifepixel but have used their services.
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Mako Koiwai
Talk/email Bill Bennett, ASC … who shot that Audi spec spot with the IR Alexa.
https://vimeo.com/93503055 Making of: https://www.youtube.com/watch?v=H6WlczFpnFI makofoto, s. pasadena, ca
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Mako Koiwai
Talk/email Bill Bennett, ASC … who shot that Audi spec spot with the IR Alexa. https://vimeo.com/93503055 Making of: https://www.youtube.com/watch?v=H6WlczFpnFI *********** You can see the added IR flare and haze … Can your post use the Adobe De-Haze function to help with the veiling? makofoto, s. pasadena, ca
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