Professor Wood's House

I was delighted to receive an email recently from someone with a personal connection to the house that Professor Wood lived in.

I knew the building was in East Hampton, and I knew the road as it was noted on his letterhead. But try as I might I was unable to pin the building down based on the two photographs I have of it. This one was the one published in the Century Magazine in the Midwinter Number of the Century Illustrated Monthly Magazine, published in February 1910 and was (as far as I know) the first infrared photograph to be published.

From my new contact I now know exactly which house it is. I'm told the building has been modified, which you'd expect after a century or more, but essentially what you can see in this photo (and the one in this earlier blog post) remains the same. The driveway from the road has changed, which is why I couldn't track it down with Google's Street View.

I hope to get a photo of the house as it is now so we can compare. I will let you know.

APS biography of Professor Wood

The American Physical Society published a biography of Professor RW Wood in October. It was part of their This Month in Physics History series and commemorated Wood's Royal Photographic Society lecture in 1910. (The biog says this was the first publication of infrared photographs, but that was actually in The Century Magazine in February 1910.)

If you are unfamiliar with this fascinating, and omnitalented, chap then I suggest you give the piece a read:

www.aps.org/publications/apsnews/201710/physicshistory.cfm

[Thanks to Professor Paul Feldman of Johns Hopkins for the heads up]

More on Wood's slides

I wrote about Professor Wood's lantern slides last time, and I have now found more about them. The slides were marketed by Newton & Co, and I found their 1920 catalogue on line in the Internet Archive.

This is the relevant section (click to enlarge):

So we now know that there are 47 slides and, as you'd expect, not all of them are infrared as they illustrated his talk on both IR and UV photography. So far I haven't been able to track down a set. Does anyone know of one?

Newton's also marketed a set of slides where Wood illustrated sound waves in photographs. This is a link to the catalogue.

Professor Wood's slides

This is a tale I have been waiting to tell for a while.

Regular readers will know that in 1910 Professor Robert Williams Wood, of Johns Hopkins University in Baltimore USA, published an infrared landscape photograph. The Midwinter Number of the Century Illustrated Monthly Magazine, priced at 35 cents, appeared in February 1910. In this was an article by Wood called A New Departure in Photography, which included an infrared photograph of his summer home in East Hampton. As far as I know this was the first infrared photograph (as distinct from a spectrograph) to be published. Later that year Wood presented his seminal paper on photography by Invisible Rays to the RPS in London and then went off to Italy. While in Italy he took more infrared photographs, many of which were published in the Illustrated London News in June 1911.

I had thought that Wood's actual photographs from this time were lost, despite the set from his RPS lecture being made available for hire from famous slide dealers Newton of Museum Street, London. So the ILN printed versions were the only ones available.

Surprisingly I came across a web page from Chris Fastie. His late father was a contemporary of Wood's at Johns Hopkins and had been given some slides, large format 'lantern' slides, of Wood's infrared photographs. These included some from the Italian trip, but also included one labelled 'First infra-red photograph' which showed another view of the East Hampton house.

The label on the slide of the East Hampton photo (above) is interesting:

So this claims to be the first infrared photograph; different from the first one published. There isn't a date on it unless that is part of the missing text (could that be revealed under infrared light I wonder). Wood's biography refers to the first photograph being of 'distant hazy' mountains taken in 1908 but this would seem to be a label, probably written by Wood himself, contradicting that. Definitive?

You can read a more detailed account on Chris's web page here.

The house was (and apparently still is) on Apaquogue Road and he was famous enough for there to have been a postcard produced, early in the 20th century, showing the 'Home of Prof RW Wood, East Hampton LI'. You can see it here, as part of a book of old postcards of East Hampton by Richard Barons and Isabel Carmichael and from the collection of the East Hampton Historical Society.

At this time I contacted Professor Paul Feldman at Johns Hopkins (he took part in our symposium in London back in 2010) and told him about this discovery. It turns out that Chris Fastie's father Bill was Paul's mentor at JHU and they all know each other. Then, Paul decided to take a look in what he called 'the attic' in the Physics department and found some more slides. These look to be others from the same set but,as they don't include the 'moon cave' image published in the ILN, it is possible there are more out there.

[My thanks to Chris Fastie and Paul Feldman for sending me scans of their discoveries]

Outer planets ablaze at 1.5 microns

Astronomer Mike Brown at Caltech hunts in the outer reaches of the solar system. He usually concentrates on what is called the Kuiper Belt which extends from the orbit of Neptune out to about twice as far as Neptune's orbit. He recently used the Keck telescope in Hawaii with the intention of imaging Neptune's moon Triton, but the views of the planet itself, and closer neighbour Uranus, were too interesting to ignore. The Keck's adaptive optics system, which compensates for turbulence in the earth's atmosphere, produces stunning results.

Neptune, glowing like a demonic cricket ball, shows the two distinct bands which are glowing at the imaging wavelength of 1.5 microns (1500 nm). Of course these are not really 'hot' since the surface of Neptune is -200 C and the bright bands will only be a few degrees warmer. These correspond to faint but visible features on Neptune's 'surface'.

With Uranus the main features are the rings, which stand out distinctly given the low level of radiation from the planet itself, and the spot to the top left which is the moon Miranda. The bright spots on the surface are clouds. This is notable because the 'surface' of Uranus, in visible light, is almost devoid of any features (although, as the 'northern' uranian hemisphere warms up some banding is appearing).

There is more at space.com.

RW Wood took infrared photographs of gas giants Jupiter and Saturn at the end of October 1915. He had been granted use of the 60 inch reflector at Mount Wilson and took photographs through infrared, yellow, violet and ultraviolet filters. His infrared filter had a band-pass of 700 nm, with its upper limit being determined by the plate sensitivity, which was probably less than 800 nm. In this case infrared photographs showed fewer features than visible light whereas belts were clearly shown on the violet and ultraviolet plates. (It is not possible to record a wavelength as long as 1.5 microns using photographic emulsion, so an electronic sensor has to be used, although this is not thermal imaging. However, this wavelength is still within an atmospheric window for infrared.)

You can read Wood's 1916 paper on the SAO/NASA Astrophysics Data System (ADS). It is entitled Monochromatic Photography of Jupiter and Saturn.

[My thanks to Mike Brown for permission to reproduce his images here.]

RW Wood at the Royal Institution

On May 19th 1911, Professor RW Wood presented one of the Royal Institution's legendary Friday night discourses with the title Recent Experiments with Invisible Light. This built upon the paper he had presented the previous September to the Royal Photographic Society and took place almost at the end of his 1910-11 sabbatical in Europe.

The discourses, which continue to this day, are formal affairs, as Wood reported to his biographer ...

His Grace, the Duke of Northumberland, not being available at the time, Gertrude [Mrs Wood] entered the hall on the arm of the Right Honorable Earl Cathcart, Vice-President, followed by my daughter Margaret, on the arm of the diminutive Sir William Crookes, who came nearly up to her shoulder and whose long white mustache, waxed at the ends into two sharp spikes, fascinated her. I brought up the rear. There was a brief introduction and at last I was standing behind the famous lecture table, giving my talk...

The following Friday, Wood was still in London and attended the discourse given by Marconi who was proposing to demonstrate reception of a radio transmission live across the Atlantic from Nova Scotia (a feat many still thought impossible) using an aerial flown using kites and, as Wood reported, "such a display of impressive modern electrical appliances as one seldom sees outside a World's Fair." Marconi's presentation, according to Wood, was rather monotonous. He read from a manuscript with his elbow on the desk and his head in his hand. "He appeared to be the least interested person in the auditorium ... and there were no experiments." Marconi droned on and his assistants became more and more agitated. The wind was dropping and while the morse signal from Canada was audible it would not be for long.

Despite Wood's encouragement the assistants would not dare to interrupt Marconi. So finally, when he eventually announced "We shall now listen to the signals coming across the Atlantic" the assistants could only shake their heads: the wind had dropped, the kites were down, the signal was lost.

A little tangential to infrared imaging I know, but it's salutary to remember just how much has changed in 100 years.

[With thanks to Doctor Wood: Modern Wizard of the Laboratory (1941) by William Seabrook]

Charles Edward Kenneth Mees 1882-1960

As 2010 draws to a close it is fitting I should commemorate another key player in the history of infrared photography, who died 50 years ago: CEK (Kenneth) Mees.

Mees had a doctorate in photographic theory from the University of London and was joint managing director of Wratten and Wainwright, who had produced the first commercial panchromatic photographic plates in 1906.

Mees had joined the Croydon-based firm in 1906. The father and son team of Frederick Charles Luther Wratten and Sidney Herbert Wratten brought him in as co-owner and joint managing director when they incorporated the company on the elder Wratten's retirement (before that it was a partnership with Henry Wainwright). When George Eastman set up the Kodak research laboratory in Rochester in 1912 he brought Mees over from England to run it. In order to do so he bought the Wratten and Wainwright business. RW Wood wrote to Mees on hearing the news, hoping he had "held 'em up for a king's ransom", asking whether Kodak were going to "close up every plate factory in the world" and hoping that Kodak would now turn out "uniform plates for scientific work". Mees wrote back to reassure Wood, saying that "we shall be able to make even better plates for scientific research than we can make at Croydon".

It is possible that Wood and Mees were acquainted by letter before Wood's European sabbatical in 1910-11, but they clearly became friends and corresponded until at least the early 1950s. In 1910 Mees was an ordinary member of the council of the Royal Photographic Society, and he chaired the Traill-Taylor lecture meeting where Wood presented his Invisible Rays paper. Wood's contact address was listed as c/o Wratten and Wainwright in the RPS exhibition catalogue and it would have been Mees who provided Wood with the infrared-sensitive plates he used on his Italian travels in 1911.

Mees also made use of infrared-sensitive plates himself. The Kodak Research Laboratory archive at the University of Rochester contains thirteen photographs (negatives and prints) taken in Portugal in 1910 by Mees using Wratten and Wainwright infrared sensitised plates (one of which was included in the Infrared 100 Exhibition). The images were taken through a Wratten 88 red filter with five-minute exposures and some show the characteristic dark skies and bright foliage that we now recognise in infrared photographs. However, in his 1936 book 'Photography' Mees credits Wood with taking the "earliest photographs of landscapes by infra-red rays", presumably referring to the images from Wood's 1910 publications.

I won't go into further biographical details on Mees as I can point you to two good sources. One is from the Croydon Camera Club, of which he was a member (explore the Who is Dr Mees item in the menu), and the other is the Image, the bulletin of George Eastman House.

Finally, and nothing whatsoever to do with infrared photography, George Eastman House archives hold a 1922 note from Wood to Mees, affording a written introduction to one Leopold Mannes ...

who has worked out a system of color-photography which appears to me to have some novel features which I think will interest you and perhaps interest your company. It occurred to me that you might offer him the facilities of your laboratory for a few days ... The process is quite simple, and the results which I have seen look promising.[Ref]

Mees did indeed provide facilities to Mannes and his colleague Leopold Godowsky Jr to work on their colour process, which eventually became known as Kodachrome. This iconic slide film was discontinued last year and the last-remaining development facility closes its doors today, at the end of 2010. So it goes.

Snow and the Wood Effect

As snow falls here in southern England for the second time this December I thought it appropriate to say a little about the Wood Effect. Named after Prof RW Wood, this is the brightening of foliage seen in infrared photographs that can often look like snow, first seen in his photographs from 1910.

The phenomenon had been observed before Wood, but not in an image, by Ogden Nicholas Rood, professor of physics at Columbia University, in his book on colour published in 1890 (or earlier). However this was based on spectrographic measurement of 'green' leaves and not photographic observation.

Willstatter and Stoll produced their theory of leaf reflectance in 1918 in their book Untersuchunger aber die Assimilation der Kohlenseture published in Berlin, and much of the literature on this was published in Germany. Not much is freely available on the web, although Mecke and Baldwin wrote about leaf reflectance in infrared in a 1937 paper which is available as a PDF (from Die Natlirwissenschaften in German).

Basically, the W-S theory says that light is reflected around within the internal structure of a leaf. Some eventually passes through and some is reflected back. Near infrared is not attenuated by the chlorophylls in the leaf as they are transparent at these wavelengths. The physical structure of the leaf is similar to that of snow, which is why infrared photographs can often look like snowy scenes. Unhealthy or dead leaves do not reflect so much because of changes in the internal structure, so the amount of infrared reflected by foliage can be used as an indicator of plant health.

Allen, and Richardson (Applied Optics Vol 12 #10 1973 behind paywall) explored the Willstatter-Stoll theory using ray tracing. This was a cumbersome process with 1970s computers and they were unable to do much, but they concluded that the theory predicted more transmission of light through the leaves than ray-tracing predicted. They concluded ...

The W-S model can be easily improved, however, by introduction of more intercellular air spaces. The modified W-S model promises to be an excellent representation of physical reality. Accurate predictions, however, require an inordinate amount of computer time.

Jacquemoud and Ustin, from Paris and California respectively, looked at modelling the optical properties of leaves in a paper from 2008 that is available online. They refer to a near-infrared plateau between 700 and 1100nm. Here ...

biochemical absorptions are limited to the compounds typically found in dry leaves, primarily cellulose, lignin and other structural carbohydrates. However, foliar reflection in this region is also affected by multiple scattering of photons within the leaf, related to the internal structure, fraction of air spaces, and air-water interfaces that refract light within leaves.

They don't call this the Wood Effect because, like most of the earlier papers I mention, they consider the optical properties across more wavelengths than infrared. However Mecke and Baldwin refer to the brightening of foliage in infrared as the Chlorophylleffekt.

So where is the earliest reference to this as the Wood Effect?

Strangely, this also seems to be in a German publication, in an article by someone named Marmet in a journal called Photofreund, (reference 18: 289-90, No. 15, August, 1938). I have seen this cited in a literature list produced by Kodak at the time, but not the original article itself.

The hunt continues.