Monday, 13 February 2017

Infrared forensics


Infrared imaging has applications in forensics. Sometimes this is because an infrared image can show variations in an object that are otherwise invisible (which applies to UV as well of course), sometimes because changes in the appearance of something under IR can show up a surface artefact, such as a fingerprint. I'm sure there are more, but I have much to learn in this area.

A recent email alerted me to a somewhat sideways use of IR in forensics, where photographer Robert Schults spent a year documenting work at the Forensic Anthropology Center at Texas State University. This seems to be basically Bones meets Silent Witness, including a 'body farm', where decomposition is studied. Robert used infrared photography in this project.

Jayme Blaschke, who emailed and works at the university, worked with Shults for more than a year on this project, along with the staff of the center. He tells me that the camera was a Leica converted with an 830nm filter (Jayme's recommendation ... good call).

You can read more in a New York Times blog piece on the project, called Photographing the Science of Death and Decay. Robert Shults' own web site is www.robertshultsphoto.com. Wired have a story with a fascinating set of images as well ... scroll down for the text. (They mention an IR converted Fujiflim X-Pro 1.)

[Image from National Institute of Standards and Technology (NIST)]

Monday, 7 November 2016

Two years to James Webb ... and counting

Once upon a time infrared was regarded as being the new astronomy. There was even a book of that title, published in 1975 and written by David A Allen. By 2014, and David L Clements' book Infrared Astronomy - Seeing the Heat, infrared was dominating the field. No longer the new astronomy, now it is astronomy.


As the BBC news web site pointed out, last week marked two years until the launch of the James Webb Space Telescope (JWST). This is the replacement for Hubble, and is a much more powerful/sensitive device. The mirrors and optical components are now assembled and ready to be tested. It's a reflector. Radiation hits the main mirror, 6.5 metres across, is then reflected and focussed onto a much smaller secondary mirror in front of the main one and then reflected onto sensors at the centre of the main mirror. You can see this in the photo above.

The JWST will be sensitive to wavelengths long enough to see back to the early days of the universe. It's basic doppler effect: as the sources of light move away from us at increasing speed, the light we see from them lengthens in wavelength towards red and beyond (hence red-shift). Because the universe is expanding, the further away from us an object is, the faster it is moving away from us. [Good pub question: where is the centre of the observable universe? Answer: where you are.]


This is one of its sensors, for NIRCam - 2048 by 2048 pixels for near infrared wavelengths between 0.6 and 5 microns (600 and 5000 µm).

NIRCam is one of four instruments: NIRCam, NIRSpec, NIRSS and MIRI. MIRI images wavelengths between 5 and 28.5 microns with a resolution of 1024 by 1024 pixels. This is a gross oversimplification, and sections 20 to 23 of Nasa'a scientific FAQ give much more information about the cameras.

If you're interested in more fine detail about the NIR system, then try this NIRCam Instrument Overview paper from the University of Arizona. Nasa has a set of web pages, Explore the James Webb Space Telescope, with copious resources.

[Photos courtesy of Nasa]

Tuesday, 1 November 2016

Ron Rosenstock

Just a quick post to draw your attention to the work of Ron Rosenstock. He's an American photographer who is a follower of Ansel Adams (which really shows in his photos) and was a student of Minor White. A solid provenance.

He does take other kinds of image but he does have a significant body of work in infrared, which I'm just starting to explore. He has produced a book called The Invisible Light, which reminds me I still have to do some work on my site of that name.

Ron's web site is www.ronrosenstock.com.

Monday, 24 October 2016

Unseen book launch in London on Thursday

Ed Thompson's fascinating book, The Unseen, which I recently wrote up, is being launched this week. Unusually, the do is an open house and might provide an opportunity for an infrared get-together ... I certainly plan to go.

The place is the Photographers Gallery Bookshop, 16-18 Ramillies St, London W1F 7LW. You might know this as that street with steps at the end leading down from Oxford Street. Timing is between 1800 and 2000 on Thursday 27th October. Ed says ...
"I will be holding a free raffle and giving away prints, original spreads from the book when it was printed and other cool rare stuff to do with the project."
Coincidentally, last time I went to the Photographers Gallery was to see some of Richard Mosse's infrareds from the Congo ... but in that case the book was unobtainable.

Monday, 10 October 2016

Simon Marsden exhibition in Chelsea (London)

If you are heading down the Kings Road between October 28th and November 4th, I recommend you drop in at number 259. That's the shop and gallery of Green and Stone and they are hosting an exhibition of Simon Marsden's infrared photographs.

Being a Kings Road gallery it's also an opportunity to buy a print from the ever diminishing stock of prints made by Sir Simon himself ... or books (some signed), the 2017 calendar, or cards. (I will admit, sadly, that my wallet tends more towards the latter.) I have to admit that besides the print of Moydrum Castle he kindly loaned to the RPS for inclusion in our Infrared 100 exhibition, I have not seen any of his prints 'in the flesh', and he always saw the printing as a key part of his work. Both composer and player, as Ansel Adams might have said.

Opening hours are 0900 to 1800 weekdays, 0930 to 1800 on Saturday and even 1200 to 1800 on the Sunday. There is also a late night opening on November 2nd until 1930 (maybe see you there?). The Green and Stone shop has been in Chelsea for almost 90 years and started life within the Chenil Gallery (apparently situated between Chelsea Town Hall and the Six Bells pub), whose directors were Augustus John and Bernard Shaw, before moving to the present site opposite Carlyle Square in 1934.