Current Recommendations for Aura Photography of Buried Metals

A Canon EOS 350D (Rebel XT) DSLR camera or EOS 400D (Rebel XTI). Used cameras can be obtained quite cheaply.

A Canon Zoom 18-55mm EF-S ‘kit’ lens (normally supplied with camera). Set the focal length 24mm or above as low settings tend to cause a reflection of the lens to appear in the photographs.

A Cokin square filter holder, P series with adapter ring to fit lens (58mm diameter).

A Cokin P007 720nm Infrared filter. Cokin now only manufacture a round IR filter, which will only work in its own slot next to the lens on strong targets. To use this filter with the kit lens on small targets it is necessary to carefully cut or file two small flats on opposite sides of the filter ring so it will slide into the square slots in the holder.

Mount the holder onto the lens and fit the filter in the centre slot of the three square filter slots in the holder (the slot nearest the lens is for a round filter). Set the camera on automatic, no flash (that’s the selector turned fully clockwise). Let the camera autofocus through the filter. All other camera settings should be on automatic/default.

For best results the air temperature needs to be above 50 degrees F / 10 degrees C. Shoot in daylight at right angles to or away from the Sun although the Sun does not need to be shining.

Good results can be obtained with the camera hand-held but marginally better results might be achieved on small targets by mounting the camera on a tripod/stand.

The viewfinder must be kept covered either by the photographer’s eye (hand held) or a black cover if tripod mounted.

Strong auras can be seen on the camera’s backscreen but for weaker auras post process the images with Canon’s Arcsoft Photostudio (5.5) using the enhance facility.

Please note: Canon have upgraded their sensor a number of times and Canon cameras other than the two above may not work in the same way or at all for aura photography.

Also the internal IR blocking filter must not be removed.

The macro lens is optional for small targets or long distance but Sigma 105mm is the recommended macro – most others have not been tested.

There are Free videos here:

Finding Buried Treasure with Digital Cameras:

Filter and camera setup for photographing treasure auras:

Part 1 Photographing Infrared Pictures over buried Silver coins:

Part 2 Photographing Infrared Pictures over Silver coins:

The Successful Treasure Hunter’s Secret Manual is available in print (softcover) on Amazon here: https://amzn.to/3SCtchK

Or Kindle or Hardcover here: https://amzn.to/4fxtSig

Or most digital formats here (epub mobi pdf rtf lrf pdb txt): 

https://www.smashwords.com/books/view/126811

Or most popular E-readers here: https://books2read.com/u/baELrv

Diamond Orbs

In TheSuccessful Treasure Hunter’s Secret Manual, I looked at thermal and electrical conductivity as a possible explanation as to why some metals produce stronger auras than others. What I discovered through experimentation is that different metals produce different auras and fortunately precious metals produce the strongest auras. In other words a smaller amount of gold or silver will produce an aura than is the case with base metals. This stuff is so cutting edge that I’m afraid I don’t know all the answers. I do recall that when I was doing a lot of beach treasure hunting in the summer evenings, when the crowds had left, that coins coming out of the sand were always quite hot to the touch. The mechanism is presumably emission of infrared radiation selectively absorbed by metals from the sun although it could just as likely be metallic interference with the earth’s magnetic field. It doesn’t matter too much, as it is results in finds that we’re after, not a degree in physics. A useful way of comparing metals seems to be thermal and electrical conductivity, I must stress these may not be the only factors or even the correct factors that determine aura strength but they do tie in quite nicely with my observations.

Silver has a thermal conductivity of 420 Watts per metre-Kelvin and an electrical conductivity of 62,000,000 Siemens per metre. Pure copper has a thermal conductivity of 370 W/mk and an electrical conductivity of 59,500,000 S/m. Gold has a thermal conductivity of 315 W/mk and an electrical conductivity of 45,000,000 S/m. Pure copper has conductivities in between gold and silver, however copper is normally found alloyed with zinc or tin forming brass or bronze respectively, which have much lower conductivities, typically a thermal conductivity of 125 W/mk and an electrical conductivity of 15,000,000 S/m. Soil, sand and water have thermal and electrical conductivities around 1 W/mk / S/m or less. Diamond, interestingly has the highest thermal conductivity of any known substance at 1000 W/mk but such an extremely low electrical conductivity it can be considered to be an insulator. Unfortunately I couldn’t afford a large heap of diamonds to test whether they produced auras but I said it might be something worth looking out for. I was sent the photo from a reliable source who claims it is a diamond aura. I must say it is a very unusual aura photo and I haven’t seen anything quite like it before. I would like to see a photo of the diamonds though, which might be available in due course.

Piggyback Cameras

Paul, from Australia, told me (and sent photos) of how he had mounted an Olympus D-360L camera onto the Canon 350d and can now take accurately pointed photos using the Olympus camera's view finder. This idea is working very well, also the Olympus is very useful being able to take a normal photo of the target area at the same time as the photo being taken by the Canon. You can actually see the area clearly that you were looking at which is rarely the case with the Cannon infrared image. Ideally you would hope to get the small orb auras, without a filter, on the Olympus to confirm the auras on the Canon although there is a small snag here in that the Canon seems to work best in the early afternoon while the Olympus seems to prefer low light conditions at dawn or dusk, like the Polaroid. Nevertheless it is a good idea worth pursuing and having a normal image in tandem with the IR image is useful, although that could be achieved with any compact, with a viewfinder, similarly mounted. Bear in mind that the lens on the Olympus is offset so the Olympus needs to be skewed slightly to capture the same view as the Canon. Stand mounting the set-up would be preferable.

Phot-R 1/4"-20 Aluminium Dual Nuts Tripod Mount Screw to Flash Digital Camera Hot Shoe Adapter

This is the adapter I used in the set up, they come with one or two nuts; although I prefer the two nut version as it holds everything more securely. The Canon’s pop-up flash is deactivated by fitting the mount, in case anyone was wondering.

Airplane Hunting

 Bristol Beaufighter firing rockets

As Chairman of The Swale Search and Recovery (metal detecting) Club I was approached recently by an up-and-coming air museum to help look for wreckage of a WWII Bristol Beaufighter that had crashed on a local muddy foreshore during a training exercise. It was believed, or hoped, that there was a substantial amount of wreckage remaining although little had been seen above ground for some considerable time.

For the initial search I organised a party of half a dozen metal detectorists to search the area, at low tide, around where the plane was thought to have crashed, which the museum assistant marked with a clump of stakes. While plenty of spent ammunition was found, not one single piece related to the plane emerged, although the tide had not been as low as we would have liked.

For the second search, at a predicted lower tide, I took my aura camera and long lens instead of a metal detector and let the others carry on metal detecting while I stood at the marker stakes and proceeded to photograph the exposed foreshore piece by piece in a one hundred and eighty degree arc around the stakes. On dry land I could have linked the camera to a laptop and analysed the photos on the spot, but out on a tidal foreshore, it would not be a good idea so I just used the camera and would analyse the photos at home later. Although there were a few permanent seamarks to help frame the photos, it was mainly guesswork where I was pointing the camera as featureless foreshore and open sea all looks the same. With the benefit of hindsight I could have used a compass and obtained a bearing for each photo. An assistant to use the compass to line me up for the photo and to note the readings would be a great help. Again the detectorists found only spent ammunition and nothing that could be specifically related to the plane.

I downloaded the photos at home and enhanced them with Arcsoft Photostudio. I was pleased to see that there were areas showing an orange aura (top photo) as well as areas showing no aura (bottom photo). I assumed I had taken photos fairly evenly around the arc and nominally assigned compass points to the aura photos. That gave me one search area approx North to Nor’-Nor’-East and another due South.

Armed with this information I organised another search, although the detecting party had now reduced to three only. Two of us went searching to the North and one to the South. We did not know how far away the targets were but guessed they would be less than 200 yards (or metres) as that was the optimum range I had been able to pick up a large target in the past. It would be possible to walk in the direction of the auras with the camera, particularly if there were compass bearings, and to re-photograph them at say ten-yard or metre intervals, which could be measured by pacing or a surveyors tape. Of course this would require another at-home analysis session to determine at which point the aura image is lost and determine that the target would lie between there and the previous ten-yard point where the image was captured. A further session on the site would be required to make the final location and recovery. Nevertheless we had some results. The South searching detectorist recovered a part of the plane’s ammunition box, meanwhile the two of us searching northwards discovered a 60lb rocket each, part of the plane’s arsenal. I also recovered a small piece of aircraft battery. So by using aura photography, we had actually started finding what we were looking for as well as defining where to look on future searches.

Part of ammunition box

One of the rockets recovered in two parts (dummy warhead at bottom) and minus fins

A Beaufighter being armed with rockets

In Search of King John’s Treasure (Part 2)

The only field that produced a good aura was the same field that had given the curious orbs with the camera on the AV setting. While not the recommended setting, it does indicate that other camera settings work – perhaps as good or better. We had photographed the field from different points on adjacent sides of the field and obtained auras in the same place from both points and with both lenses, so there is definitely a substantial quantity of metal buried here, which may be silver from the colours obtained in the photographs. I should perhaps mention that this is not the field that Garry Brooker indicated but it is close by.

We now needed to contact the landowner to discuss the possibility of undertaking a survey to try and establish what is buried there and at what depth. It has now become quite easy to use the Land Registry online: https://www.gov.uk/government/organisations/land-registry to establish ownership and in this case it only took a few minutes. Writing a letter to the landowner took somewhat longer and as yet we have received no reply. Still no news is good news, they say! Meanwhile Aquila is seeking Yamashita’s gold in the Philippines so I am awaiting his return before chasing this project up…

Olympus Digital Cameras

We have found three early Olympus digital cameras that are capable of photographing auras. The earliest is the D-360L, which will produce tiny orb auras and does not even need a filter. My friend Kybob has made a video of this camera in action: https://youtu.be/USOH2GnspHg

Note that there is a vehicle in the background in some of the shots, which will produce auras in its own right, being a substantial chunk of metal. This is the second video in a two part series. Part 1 covers the Canon camera: https://youtu.be/-4u9F3qOrmcThe other two cameras: D-490 Zoom and C-460 Zoom del Sol both need a filter. I am using 850nm, 90% pass filter material successfully in the Cokin Compact Camera holder: Amazon link: https://www.amazon.co.uk/Cokin-Digi-Holder-Cat-BAD700/dp/B0000AQ4N1/ref=as_sl_pc_as_ss_li_til?tag=trutreboo-21&linkCode=w00&linkId=4fb7b0a2b30130c6c5dd74146690004b&creativeASIN=B0000AQ4N1

I have just been informed that Cokin also make a magnetic filter for compact cameras: Amazon link: https://www.amazon.co.uk/Cokin-Magnetic-A-Holder-BA400MM/dp/B000T8Z3Y6/ref=as_sl_pc_as_ss_li_til?tag=trutreboo-21&linkCode=w00&linkId=ddc2a72f2e3b2827ca347a92d4405d6d&creativeASIN=B000T8Z3Y6

However, when I used a round filter on the D-490, attached to the front of the lens with poster putty, I found I needed a 950nm filter.The orb auras become larger as the megapixels increase, the C-460 ZdS at 4.0MP produces the largest orbs of the three.

I haven’t tested all the early Olympus cameras and many can be bought so cheaply now, they may be worth buying just to test. Ideally look for one of the above models, which we know work. If you want to try another model, get one which has a viewfinder or viewing port as it is impossible to use the backscreen with an IR filter in front of the lens. I can tell you that I have tried the C-460 and D-545, which did not produce auras on my test site.

In Search of King John’s Treasure

A few months ago, out of the blue, an Australian, Garry Brooker, inventor of Rangertell, long range metal locators, gave me GPS co-ordinates, which he claimed to be the possible location of King John’s treasure. He didn’t tell me how he obtained this precise location, just that he and some American friends have become very accurate at locating various hidden metals using Google Earth.

I had only just thanked Garry for the information, when my friend, Aquila Chrysaetos, an accomplished dowser and author, contacted me to discuss King John’s treasure to include as a chapter in his second book, Dowsed Treasure Locations Around The World.

We thought it would be worthwhile to go and check the site out, so we pooled our dowsing and research resources and headed off for sunny Lincolnshire. Aquila had dowsed a number of targets in the area, including several quite close to Garry’s co-ordinates. We had been fortunate to get accommodation within walking distance of the fields, so after a hearty breakfast we set out photographing fields. The fields were under crop, so we could only photograph from the public roads and tracks running alongside.

I use both the Canon 18-55mm lens and the Sigma 105mm lens so I get two different takes on any target and I need to get a good aura with both to confirm a good target. So it was a matter of taking  enough shots with one lens to cover the field and then changing lenses and repeating the shots, plus one shot without the filter to identify the field later.

When photographing the second field I noticed this unusual orb formation on the camera backscreen.

It was only when photographing the third field that Aquila commented on how slow the camera shutter was operating that I looked at the setting and realized that I had the selector on AV, which is the setting I use when photographing finds, to get the necessary depth of field. So, moving the selector to the correct Auto-No Flash setting, we had to retrace our steps and take the shots of the three fields again. As it happens, we are both a bit overweight and undoubtedly benefited from the additional exercise!

Rule 1; always check the camera settings before taking photos!

To be continued…

Magical Treasure Hunting

This is a history of treasure hunting from the middle ages to the present day, rather than a how to book. Nevertheless, it is well researched and despite being written by a university senior lecturer, is quite entertaining, although biased towards Europe, as medieval North America is largely undocumented. The study leads to the conclusion that treasure hunting in the medieval period was all about dealing with treasure-guarding angels, fairies and ghosts, where wizards were willing to face demons in order to get rich quick and resourceful tricksters exploited greed and stupidity, all watched by profit-seeking authorities. Generally speaking, most authorities regarded treasure hunting as benign and not evil like witchcraft. In the modern period treasure hunting evolved through searching for saintly relics to today’s method’s of researching, gathering and interpreting historical clues to find the treasure.

 

Interestingly, dowsing or divining has been used throughout the history of treasure hunting and another finding I picked-up on, was that flames, particularly blue flames were claimed to appear above buried treasures. Compare this with Louis Matacia, writing in Finding Treasure Auras, (1996). “When the full moon is highest in the night sky, the Indians would see a bluish-green flame glowing above the ground in the mountain. The glowing flame appeared to grow very slowly, reaching an impressive height and then retreating to the earth from whence it came…And this is where they found the silver and gold.” It seems the phenomenon of treasure auras existed well before the invention of the camera.

 

Going back to the book, I read it from cover to cover and found it a good read. First printed in hardback in 2011 and paperback 2012. The drawback, as with academic books in general, is the eye-wateringly high price. Even the E-book is priced at over £20.00 GB Pounds. You can always try and borrow the book from your local public library though.

The Colour of the Money

Buried metals interact with the earth’s magnetic field to emit electro-magnetic radiation. Radiation seems to be emitted across a spectrum of wavelengths from Near Infrared, through visible light to Ultraviolet. Different metals may have different dominant colours of radiation, as processed by the camera. This seems unrelated to the natural colour of the metal or alloy, since similarly coloured metals such as gold and brass do not necessarily produce the same colour radiation or aura. Colours can also change according to the size of the target. A single gold coin can produce a red aura and a bucketful will, presumably, also produce a red aura; a handful of iron junk, on the other hand, will produce a yellow aura but a lump the size of a car engine will produce a red aura. The colours do not work perfectly, unfortunately, but you can generally say that if the aura is not red then it will not be gold and you probably will not miss gold buried in an iron box. These colours are typical of the Canon camera using a long (Sigma) lens, which does not normally produce orbs.

The shorter Canon kit lens almost invariably produces an aura in the form of coloured orbs with a background colour. I believe the orbs form because of the geometry of the lens and is a function of radiation bouncing between the internal IR blocking filter or hot mirror and the rear of the external IR filter. Gold tends to produce multiple blue orbs on a red background and again, the size of the target may affect the numbers of orbs and colours. 

Filters and Holders

I still get asked many questions about infrared filters so I am going to cover a few points here.  The Canon camera is a Single Lens Reflex, which means you view directly through the lens, not a viewfinder, so when you put a nearly black infrared filter in front of the lens, with the best will in the world, you cannot see a thing through it. You can use screw on filters but I don’t recommend it. You will need to have the camera mounted on a stand and if you keep taking the filter off to view the target, then screwing it back on again to take the shot, not only is it a real pain but sooner or later you are likely to cross-thread the coupling and have to replace the lens and the filter. 

I do recommend the Cokin type square filter holder (above), you only have to screw it on once and you can slide the filter in and out at will. Simples! It is not necessary to buy a Cokin brand holder, there are plenty of low-priced copies available, that are perfectly adequate for our purposes, such as the Polaroid one above, which you can buy on Amazon.co.uk for £3.99 http://amzn.to/2r6M79y  You will also need an adapter ring to fit the holder securely to the camera lens. The Canon kit lens is 58mm diameter.

The holder has four slots. The slot against the lens is designed to take the round filter and this position will probably only work with a very large target, if at all, as we need a light and air gap between the lens and IR filter.

The remaining three slots are designed for square filters. P size IR square filters are no longer manufactured by Cokin because, they say, unwanted reflections occur if the filter is not against the lens. Suitable square filters may be available from other manufacturers or available in sheet form that can be cut up into squares..

If you have a round filter then it is desirable to trim two flats opposite each other so the filter will slide comfortably into the ‘square’ slots. I advise putting the filter in the centre ‘square’ slot.

You can buy this Cokin filter at amazon

You can increase sensitivity to capturing auras by moving the filter forwards away from the lens but this may cause unwanted reflections. Conversely you can reduce sensitivity and unwanted reflections by moving the filter backwards, towards the lens.

The round filter has a ‘squashed top-hat’ profile so you have a couple of extra options for changing sensitivity as it can be fitted two ways into the slots furthest from the lens.

For compact cameras, Cokin make a filter holder that screw fits onto the camera’s tripod mounting. The holder takes an A size (67mm) square filter. Cokin still manufacture an A007 square infrared filter but compact cameras like the Olympus tend to need a higher rating than Cokin’s 720nm. The solution is to buy 800nm – 950nm sheet and cut it to fit.

You can get the compact camera filter holder from Amazon Here

The Yellow Peril

A while ago a guy in the Middle East kept sending me infrared photos, taken with a Canon camera during the day, like the one above top. I had not come across this before and it did not seem to matter what we tried, the photos always came out yellow and with no sign of an aura even when using a suitable test target. The new contact who took this picture also sent a photo of the same area, taken at sunset, which produced a more usual and interesting aura image, above bottom. Now I enhanced the images, myself from straight-off-the-camera images my contact supplied me, so there is no ‘photoshopping’ or fancy editing going on here. The temperature was 23 degrees centigrade in both cases, so the yellow caste does not seem to be temperature related. At the moment, I can only put it down to an anomaly with the particular camera perhaps letting more light than normal reach the sensor but if anyone has any other ideas, I would be pleased to hear them. Nevertheless if anyone else comes across the ‘yellow peril’ you now have a solution – take the photos at sunset as we had to do with the old Polaroid camera.

Taking better aura pictures

People, animals, vehicles and metal structures (including part metal structures like steel reinforced concrete) produce auras as does a lot of sky, so keep these things out of your pictures as much as possible. The tunnel effect in the picture is a reflection of the inside of the lens, it can usually be removed by increasing the focal length (the 18-55 range on Canon kit lenses). Set the focal length below maximum if you can to avoid problems with auto-focussing.

Infrared photo enhancing

I use Arcsoft Photostudio 5.5, as originally supplied with the Canon camera, for enhancing my aura photos. I have managed to keep this running on PCs up to and including Windows 7, although it does flash up a compatibility issue message at start-up. I haven’t found that to be a problem as long as I don’t use the browser function on Photostudio’s toolbar. In the past I had been told that version 6.0 did not work but I was recently told that a newer version 6.x did work. We did a few tests and sure enough I could not tell the difference between enhancing performed on 5.5 and that on the newer version, which can be downloaded free from: http://arcsoft-photostudio.en.softonic.com/

Hot Mirrors

False color infrared image of 1759 British Fort at Crown Point, New York © 2015 by cfastie and reused under a Creative Commons Attribution-ShareAlike 3.0 Unported License.

I often get asked if the hot mirror should be removed from a digital camera to photograph auras. Digital cameras are as sensitive to near infrared radiation as they are to visible light, so ALL are fitted with an internal infrared blocking filter or hot mirror. If the hot mirror is removed the camera is HIGHLY UNLIKELY to photograph auras simply because it will flood with the full spectrum of infrared and we won't be able to see the infrared generated by buried metal. Removing the hot mirror does have an application for false color photography, which may show ground anomalies but this is very different to aura photography. For aura photography, what we are looking for is the older, lower specification digital camera, where the hot mirror is less efficient then the higher spec and more up to date camera and will allow enough infrared through to show an aura in the photograph.

 

I have invited treasure hunters and researchers to come forward with their tests on digital cameras for photographing auras but unfortunately I still have no reliable information on cameras other than Canon and Olympus, although recently I have seen some encouraging results from Nikon cameras.

Orbs of Light

I get asked many questions about circles (spheres) of light or orbs some of which I can answer and some I can’t. While orbs have been seen on traditional emulsion film photographs they are mainly a phenomenon of digital photography. A digital camera has an internal ‘hot mirror’ or blocking filter to stop infrared radiation reaching the sensor and blurring the conventional photograph, as infrared focuses differently to visible light. I believe that on some (weaker) lenses the infrared is reflected back off the hot mirror onto the back of the lens and is photographed as an orb. Depending on the intensity of the infrared radiation, the reflection can bounce back and forth a number of times forming several orbs. The photo above was taken of a large target with a Canon EOS350D with standard lens and 720nm filter.

 In comparison the same target was photographed above with the Sigma 105mm macro lens, which tends not to produce orbs, possibly because of the greater length of the lens.

 Both photographs were taken during the investigation of a suspected treasure site. Unfortunately the landowners will only allow excavation by archaeologists. To go ahead in this manner would result in the finds effectively being confiscated and no reward payable.

There are other reasons for the formation of orbs other than buried metal and several books have been written about orbs claiming them to be manifestations from the spirit world. Two I have are The Orb Project and Orbs Their Mission and Messages of Hope, both co-authored by Klaus Heinemann, who is a doctor of physics. And here is a link to a website: http://paranormalresearchforum.net/2011/04/26/orbs/ There are many photos of orbs in the books, a few of which I can explain without reference to the spirit world. Apart from buried metal, there are a number of common generators of infrared, which can result in orbs such as light sources (sky), metal structures, animals and people. When taking photographs of potential treasure targets we should always avoid including any of these in the camera frame.

Here is an example. I took these evening pictures of the cable car across the river Thames in London , England , built for the 2012 Olympics and called Emirates Airline. I was using the Canon camera with standard lens but no filter or flash. I didn’t realize at the time that I had the tops of some street lamps in the frame. Now Klaus Heinemann would probably claim the orbs in the pictures are spirits joining in the fun of the cable car ride but I am convinced they are caused mainly by those street lamps and possibly some of the other lights in the picture.

Accidental Treasure Auras

 Auras can be photographed without even trying it seems.  I am grateful to Rich Labate who has given me permission to publish his photograph above.  Using a Nikon L1 pocket digital camera on automatic, with no filter, Rich was just taking a picture of the view across a valley in New Mexico. The resulting picture shows a bright green flash on the hillside – local knowledge says that there is a copper mine or copper deposit under the hill.

This is not an isolated case of auras accidentally appearing on photographs.  I was sent a photo of the site of an Iron Age village in continental Europe, culled from the Internet, which shows what can best be described as a fog patch immediately above the village site.  Similarly, my friend Dave was investigating a treasure site and turned up Google Earth aerial and street view photos of the site, which both showed a patch of isolated fog.  Unfortunately the site turned out to be a scheduled ancient monument so it cannot be investigated without government permission.

The moral of this story is to take a close look at any photographs of possible treasure sites you have, or come across and if you spot anything that looks as if it might be an aura, you could soon be digging up a fortune.

Can YOUR Digital Camera See Buried Treasure?

One of the most exciting recent developments in treasure hunting is aura photography and among the most frequently asked questions is: can my model of camera see auras? We know of a few cameras that definitely photograph auras and hope to add others to our list from the vast number of makes and models out there, once we are certain that they work. Meanwhile, here are some low cost ideas on testing your own digital camera and please let us know if your camera can see buried treasure.

The basic requirements for testing are:
A buried sample of either one ounce (30 grams) of relatively pure gold or two ounces (60 grams) of relatively pure silver. By relatively pure we mean around 90% precious metal so 22 carat gold or sterling silver (92.5%) will be ideal but if using 9 carat gold then you will need around 2.5 ounces (75 grams). Bury your sample in open ground or a planter for at least 24 hours.
Infrared filtering medium in the range 720nm to 1000nm. Digital cameras are extremely sensitive to infrared radiation and have to be fitted with an internal infrared blocking filter to prevent most infrared reaching the sensor. There is much variation in the amount of external infrared filtering necessary to photograph auras. Too little external infrared filtering produces false color infrared photographs and too much filtering results in pitch black images. Auras are photographed between false color and pitch black. The most reliable but more expensive option for testing is to buy either a 720nm infrared filter, or a range of filters, from a camera equipment supplier or Ebay. A minimal cost approach would be to use the black leading ends from exposed processed color film, which has infrared filtering characteristics (one sheet is approx 720nm; two sheets approx 850nm and three sheets approx 1000nm). These are the film pieces that were exposed to light (unless the film was loaded in a dark room, in which case the leading end pieces will be clear) when the film was run out over the sprockets during loading into the film camera. As most popular film is 35mm and some lenses are larger, you may have to mount the film in a slide or between thin card in which a suitable central aperture has first been cut.
Fix your filter material in front of the lens (try snug fit and leaving an air/light gap) then photograph your sample on a warm day, preferably above 13 deg. C / 55 deg. F with the Sun behind you. Adjust the level of filtering until you achieve a dark image that you will need to process with enhance, fix or gamma increase using photo editing software.

Beware the 'Professional' Photographer

A couple of weeks ago, I arranged for my colleague Brian to test his Canon EOS 400D (Rebel XTi), with my lenses on my buried targets. Brian is a keen amateur photographer and as such likes to take control of the camera so I let Brian shoot the targets in his own way. The results were very mixed and even using the Sigma macro lens (which gave the best results), Brian didn’t capture many auras and most shots just resulted in a ‘noisy’ blank. Strangely, shots of the same target produced auras on one shot but blank on another. My own experience was that if a target produced an aura once, all things being equal, it would produce an aura every time, so I went for a lie down in a darkened room to contemplate the problem…

Although I’m a technician by trade, I like to keep things simple especially with complex instruments like DSLR cameras so I put my camera on automatic and just point and shoot, letting the camera take care of everything, including focusing. Brian had set his camera on automatic but was pre-focussing without the IR pass filter in place (so the focus would lock on visible light), compared to my method which was to autofocus through the IR pass filter, and effectively focus on infrared light. Brian returned to retest his camera using the standard lens and autofocus through the IR pass filter. The results were great --The picture shows the aura on a single British gold sovereign coin. I used Brian’s camera hand-held and achieved an aura on all targets except the three aluminum beer cans; Brian used the camera hand-held and tripod-mounted and achieved auras on all targets. Brian achieved slightly better results than me, with tripod-mounted producing the best results and I put this down to operator technique – the more stable the camera is held the better the results.

A couple of other interesting facts emerged from these and other recent experiments. 1) The auras have definitely become stronger over the two years that the targets have been buried. 2) I removed the four gold coins for the benefit of the video and did not re-bury them. One week later we were still getting a faint aura over the empty hole.