Sunday, 24 November 2024

Tidy IR solution for mirrorless cameras

Kolari Vision have been busy. They have introduced a behind-the-lens clip-in system for filtering which allows you to swap filters directly in front of the sensor. This is especially useful for lenses which don't allow you to put a fiter in front of the lens, such as fish-eyes. Of course some lenses have special filter slots built-in but these are inherently restricted.

I had wondered whether a full-spectrum converted mirrorless camera would revert to conventional visible light work by putting an infrared-blocking filter (aka 'hot mirror') in front of the sensor/lens. After all, unlike an SLR, the exposure sensing is done from the main sensor, not from a separate system, so it will still function as normal if the 'hot mirror' has the same characteristic as the original.

It turns out that Kolari have come to the same conclusion. If you have a mirrorless camera converted for full-spectrum photography, such as a Nikon Z series, you can then add a suitable 'hot mirror' flter in front of the sensor simply by clicking it into the Kolari magnetic filter system. In that case, your camera is 'conventional' again.

One important thing to bear in mind is that if you buy a new camera and have it converted (by any facility, not just Kolari) you will probably invalidate the original warranty. So best to wait a bit.

So, two links to explore: Kolari's clip-in filters and hot mirror replacement (here as an external filter).

And while you're there, Kolari have a fascinating article about the dreaded infrared hotspots, which answers quite a few questions!

Wednesday, 10 July 2024

Kolari Vision Infrared Competition

The American infrared specialists, Kolari Vision, based in New Jersey, are running their infrared photography competition In Another Light again this year.

The competition runs until the end of October 2024, with winners notified by mid-December and is open to individuals world-wide (apart from a few places) with a range of categories and prizes. Check out the In Another Light web page for more information.

Entry is free and I'm glad to see that Kolari state that copyright in submitted images remains with the photographer. The prizes are vouchers for Kolari's goods and services, which includes infrared conversions, filters and ready-made near-infrared cameras.

Sunday, 7 April 2024

Dune movie scenes shot in Near Infrared

One of the big cinematic releases at the moment is the second part of Denis Villeneuve‘s interpretation of Frank Herbert's SF Epic Dune.

Cinematographer Greig Fraser decided to use near-infrared (NIR) imaging to show the weird environment of the planet occupied by the film's uber-villains, the Harkonnens. He had used the technique before, on Zero Dark Thirty in 2012 and Rogue One: A Star Wars Story in 2016.

While the Australian movie BRINDABELLAS | edge of light in 2016 (see below) had used RED cameras configured for monochrome IR, Dune used an ARI Alexa camera but the basic premise is the same. The usual infrared blocking filter was removed and replaced with a 'black' infrared-pass filter.

The idea with Dune was to show the unreal environment the Harkonnen's inhabited. The first film had only shown interiors but the second part required exterior shots. One significant result of this technique is the surreal look of the characters, since NIR penetrates a few millimetres into skin (and the characters are hairless) and there is the well-known look of people's eyes and the inherent high contrast.

[Photo: Dune: Part Two Infrared Copyright © 2022 Warner Bros. Pictures, Inc.]

I can point you to the following for much more information: Variety, NoFilmSchool, Kolari and ARRI Rental.

This provides an opportunity to review some of the history of near infrared in feature films.

Infrared film was a useful tool in the motion picture industry as far back as the 1920s. Kodak had produced their first infrared ciné film stock in 1925 and by 1937 it was also available from Agfa and DuPont. Agfa's was the first of what was described as the modern infrared film in that it was not a panchromatic emulsion pushed into infrared sensitivity. The new films were only sensitive to UV and blue and then to extreme red and infrared. This simplified the filter needed and a Wratten #29 (deep red) was the most common used. Sometimes infrared film was used in the making of travelling mattes (used to replace backgrounds in shots) but more often it was used in black and white movies to allow night-time scenes to be shot during the day, a technique now known as 'day-for-night'.

Not all the artefacts of infrared images were welcome however, and special makeup (usually lipstick) and set painting often had to be applied. Sometimes foliage was sprayed with green paint to hide the Wood effect and prevent shifts in tone. Paramount even painted an entire back-lot 'Brownstone Street' in special blue-grey paint called infra-red blue so that it would look the same on both infrared and panchromatic stock. The 1941 DuPont film was welcomed by cinematographers because of its lack of Wood effect and the three apparently competing emulsions had actually found slightly different and complementary niches in this specialised application.

By the 1960s the movie industry was moving from black and white to colour and infrared's abilities for day-for-night shooting were obsolete. But occasionally infrared filming was used for artistic effect.

In the early 1960s there was a curious collaboration between the Cuban and Russian film industries resulting in an extraordinary movie called Soy Cuba (I am Cuba). The director was Mikhail Kalatozov, famous most probably for The Cranes Are Flying in 1957, and the director of photography was Sergey Urusevsky. The film is a cinematic tour de force, featuring several long single-take sequences which almost defy attempts to work out just how they were done.

Much of Soy Cuba was shot using infrared film, with characteristic bright foliage and dark skies. The film stock was actually manufactured for use by the Soviet military, so it was quite a coup for the production to access some of it.

More recently, movie-maker Mike Figgis has been experimenting with low light and infrared photography using consumer video cameras with Sony's Night Shot facility. His 2001 film Hotel includes scenes done this way, to such an extent that the actors in the scenes could not actually see each other during filming.

The director of 2006 movie Wristcutters (A Love Story), Goran Dukic, had intended to use Kodak Ektachrome Infrared extensively to provide the look of the film's afterlife for suicides setting. Kodak provided unique super-16 format stock for this purpose, but after shooting some tests Dukic decided to use post-production techniques rather than infrared film. Some of the test sequences were shown on the film web site and on the published DVD. The production eventually sold off their unique stock for $300 per roll.

In 2015 film makers Glen Ryan and James van der Moezel of silver dory productions in Australia released a movie to exploit the monochrome infrared abilities of the RED digital cinema camera, called BRINDABELLAS | edge of light. It was described as “the World’s first near-infrared feature” and was shot in 4k resolution. I wrote it up in a blog post at the time, and the movie is still available on their web site.

Since most NIR-converted stills cameras can now shoot movies as well, the scope for infrared movies has expanded greatly over the past century.

Wednesday, 27 March 2024

Simon Marsden: Online exhibition and print sale

I'm delighted to have been pointed to a new online exhibition from the Centre for British Photography of infrared photographs by the legendary Simon Marsden ... subtitled Visions of a Ghost Hunter.

Here it is: britishphotography.org/exhibitions/70-simon-marsden-visions-of-a-ghost-hunter

The exhibition is online starting yesterday (March 26th) and running until April 26th 2024. There are 23 photographs of his characteristic ruins and landscapes, all exploiting the idiosyncratic style of Kodak's much-missed 35mm High Speed Infrared film.

Sadly, the £1500 price tag is too much for me but these are wonderful images and well worth a view.

The show is online because the Centre for British Photography have now closed their gallery in central London as the lease ended early; but this was apparently only ever intended to be a temporary space. Follow their web site for updates.

Sunday, 24 March 2024

Ed Thompson Infrared Story

Back in September 2016 I wrote about a colour infrared project by documentary photographer Edward Thompson called The Unseen.

Ed has been building up a YouTube channel called Pictures On My Mind and this includes some explanations of the work he did with some of the last remaining stock of infrared Aerochrome, which was basically the same as infrared Ektachrome EIR.

The latest video outlines at length the shooting he did in Pripyat, Chernobyl, and included in The Unseen. This part of his infrared journey started with finding out that false-colour infrared film was widely used in forestry. The normal red look of healthy foliage would tend towards magenta when the foliage was 'stressed' and it was a good way of determining forest health from a distance.

Alongside the Chernobyl video is another one going into more detail about other parts of the Unseen project, but because it includes some nudes (to demonstrate IR's ability to allow you to see a few millimetres under the skin and to echo demonstration shots published by Kodak) this video is restricted and Ed has had difficuly making the most of his whole channel.

This video passes on a couple of interesting pieces of information about Ed's technique. One is that, certainly until he was totally au fait with the idiosyncratic film, Ed bracketed the shots. I always found this was essential for any infrared film but I have come across photographers who are able to get it spot on without bracketing. The other is that he says in the video that he used a visually-opaque R72 filter to get the very deep reds that he achieved. Usually you'd use a minus-blue filter (yellow) with EIR. Those reds are mind-blowing!

Each section of The Unseen represents different applications of infrared photography with others including art investigation and restoration and medical imaging. (In fact the third edition of the standard text, Photography by Infrared, was written by Lou Gibson, who was a pioneer of medical photography.)

So I can recommend Ed's YouTube channel and especially The Red Forest of Pripyat Chernobyl. Enjoy!

Thursday, 8 February 2024

Uranus is not as boring as we thought

The conventional view of Uranus has been that its apparent surface shows few, if any, distinguishing features. The images from the Voyager 2 probe in the 1980s showed what Nasa describes as a "placid, solid blue ball".

The James Webb telescope, using infrared wavelengths rather than Voyager's visible ones, shows something else. In this light the north polar ice cap becomes visible. (Uranus, bizarrely, rotates almost at right angles to all the other planets so the north pole is, in this configuration, pointing towards us.) Some storm clouds are apparent as well, and the planet's rings show up clearly.

I've not been adding to this blog of late, so I realise I am a bit late with this as a group of photos were released by Nasa back in December 2023. The Nasa web page has copious information about the set, which includes wider field photographs (also larger than the image above).

That Nasa page doesn't give information about the wavelengths used for the image. There's a more detailed report from Scientific American, which notes that image is built using wavelengths of 1.4, 2.1, 3.0 and 4.6 microns. Since photographically, we're more used to nanometres this means 1400, 2100, 3000 and 4600 nm.

[Image credit: NASA, ESA, CSA, STScI]