Introductory Infrared
Photography and Paranormal Applications
By Andrew Selfridge
Originally published for Paranormal
Underground Magazine, September 2009, Vol. 2, Issue
9
Ghosts and spirits seem to occupy an unseen world that is
all around us, interacting with our own at their leisure.
What if we were able to see into that unseen world, even
if only just a small portion? Would it reveal answers to
these mysterious phenomenon or would it merely eliminate
yet another small portion of the electromagnetic spectrum
as a candidate for spirit observation?
Being able to see in other spectrums of light has
often been thought to give the observer an edge when
dealing with visually documenting paranormal phenomena.
One popular area for such study is infrared photography
and video. Infrared (IR) refers to the spectrum of light
wavelength located between 700 and 1400 nanometers (this
figure fluctuates depending on source but that is the
core range of the near-infrared). Actually, wavelengths
in this range, although commonly referred to as infrared
in the industry and where applied to paranormal research,
is actually known as the near-infrared (NIR). In the
context of paranormal applications, these terms tend to
be used interchangeably, and although it is a bit of a
misnomer, I will refer to the near infrared spectrum as
IR or infrared for the duration of this article.
What is so special about this spectrum of light? Aside from the fact that we can't see it with our naked eyes (actually, dark-adapted eyes can detect near IR at the lower end of the spectrum) it is often thought that spirits can use this spectrum of light to manifest. Perhaps this mentality was borne from the famous infrared photo of "John" (or Johann, depending on source) the supposed playful spirit that reportedly haunted the Toys-R-Us store in Sunnyvale Ca. The case received a lot of publicity and controversy in the late seventies, but one thing that came from the case was a grainy black-and-white infrared photo showing a figure leaning against a shelf. Witnesses described this figure as the ghost of "John" leaning against an aisle rack and they reported the figure wasn’t visible when the picture was taken. Another popular infrared photo was taken at the famous Bachelor's Grove cemetery in Midlothian IL. The photo, a black-and-white IR shot, depicts a woman sitting on a bench in a white flowing gown. The picture was taken during the daylight and witnesses again reported no one present in the shot while it was taken. This shot is commonly referred to as the "Madonna of Bachelor's Grove".
The popularity of the Niteshot™ feature on Sony
branded cameras is also a testament to IR popularity in
the paranormal field. With this technology becoming
cheaper and easier to put in the hands of the average
consumer around 1998, total dark infrared videos became a
common addition in many paranormal investigations. IR
video served two purposes for the investigator. It
allowed for the complete illumination of total darkness
(0 lux) environments while also allowing the investigator
to see any infrared video anomalies that might be present
during the video. This was an extreme help to
investigators everywhere, because the clarity afforded by
this system was far better than night vision scopes using
image intensifier technology. Prior to these Sony
systems, if an investigator wished to film in total
darkness, he or she would have to adapt a night-vision
scope to their video equipment. The problem with this is
that most nightvision scopes that are within the price
range of the average investigator were referred to as
"generation 1" devices. Generation 1 night vision scopes
used a vacuum tube image intensifier to amplify light.
This optic system resulted in a very strong fish eye
effect, with distortion and chromatic aberration at the
outside edge of the field of view. This also resulted in
clear, distortion-free viewing only in the center 30
percent of the picture. This is why the Sony systems were
welcomed with open arms from investigators everywhere.
There are limitations to the Sony Niteshot™ systems that need to be taken into consideration. Despite the fact that their picture quality was far superior to the night vision scope method, their sensitivity to total darkness without some form of infrared illumination was abysmal. These systems required ambient light, in the form of infrared illuminators, to function in 0 lux. Sony addressed this shortcoming with the SuperNiteshot™ feature where the image was brightened by extended exposure. The problem with using this feature in any type of video is that fast moving objects created ghosting artifacts, and usually normally benign looking objects such as bugs or dust took on a Spielberg-like poltergeist visual effect. Sony also introduced the Niteshot™ feature into several models of digital point-and-shoot cameras, allowing for infrared photography. These can also be used for daylight IR photography, but more on this later.
In the past, if you wished to photograph the IR
spectrum, it usually meant that you needed a single-lens
reflex (SLR) camera and special film. Prior to the advent
of digital CCD and CMOS sensors and digital cameras in
general, advanced photography required the use of an SLR
camera so that exposure times and aperture could be
controlled manually. Even after digital photography took
off, most consumer based systems were point-and-shoot
with limited control over shot variables. This meant that
if you were interested in IR photography, you still had
to use the SLR camera and IR film. Using infrared film
was especially cumbersome due to special handling
instructions. Infrared film needed to be kept
refrigerated before loading. Loading and handling of the
film was to be done in darkness, and developing as well
as initial purchase were slightly more expensive than
regular film. These factors made using IR film a hassle,
and discouraged many folks from trying to use it.
Fast forward a few years and you find that digital photography has revolutionized the way people photograph and document paranormal research. One unexpected side effect of the digital revolution was that the CCD and CMOS image sensors were highly sensitive to the IR range (and ultraviolet as well). Manufacturers noted that this would saturate their images, so they placed a piece of glass coated with a special optic film known as an IR cut filter. Basically it allowed only visible light wavelengths to pass through to the image sensor. This cut filter would stabilize color levels in visible light, but basically makes infrared photography all but impossible. In Sony Niteshot™ products, this filter (sometimes referred to as a hot mirror) is removed from the image sensor and the color values are dropped in favor of that green hue (green is used in most night vision applications because the human eye can distinguish more shades of green in low light than any other color). Early adopters of Sony products also found that with longer exposures and a good infrared filter, certain materials of clothing became transparent in infrared. Afraid of what that would mean for Sony's liability when these cameras were used improperly, the company restricted the camera's aperture and exposure settings when in Niteshot™ mode via firmware. With the new camera settings in effect, Niteshot™ mode restricted the user to only taking pictures at night.
Digital camera manufacturers have done a fine job
of making sure that their products are used in visible
light applications only. Since we know that the image
chips are capable of infrared and uv sensitivity and that
they are only being blocked by the use of a mechanical
cut filter, modifying these cameras for shooting in the
infrared. If you removed the cut filter and replaced it
with a piece of glass (so as not to change the focus of
the optic system) and used a commercially available
filter, you could effectively shoot in the infrared
spectrum without the use of special films. There are
services available for those folks that aren't
technically gifted with taking their camera apart and
modifying it. They will modify it for a charge (usually
pretty expensive) and you can shoot IR at your leisure.
It should also be noted that if you modify a digital
camera for use with IR photography, that it is a
permanent mod. You won't be able to use it for anything
other than IR photography again (unless you keep the cut
filter and replace it, but that rather defeats the
point). If you don't think that you are technically
gifted enough to modify a digital camera for IR
photography, fear not. At the end of this article I will
post a link to a simple IR camera hack that virtually
anyone can do in about fifteen minutes to a half hour.
With digital cameras, you basically have two methods available to conduct IR photography. Removing the IR cut filter above is the most effective method, producing the best results. Another method is what I like to call the "brute force method". Most all digital cameras are so IR sensitive that there is a little IR bleedthrough even when the cut filter is still in place. You can easily test this by holding up a television remote control to the lens of the camera and pressing a button. If the infrared emitter on the remote control sufficiently lights up in a strobe light pattern, you should be able to use the brute force method with your camera. Basically, with the brute force method, you will place your infrared filter on the outside of the lens and setup the camera for a long-exposure shot. This means that you will have to use a tripod, and this is not optional. With the long exposure shot, you will undoubtedly have to experiment with ISO settings (less ISO, less grainy) and white balance settings (tungsten works best for me). Take the photo trying your best not to nudge the camera when you press the button. A remote is especially helpful here, but if one is not readily available, you may wish to use the timer function on your camera to make sure that you don't touch or vibrate the camera during the exposure. Your photos using this method will be dark, and color shifted. The color channels have no meaning in the IR spectrum, so most will oversaturate with false color. Just desaturate and change to black and white. This is the hardest and least rewarding method of infrared photography, and my least favorite. Remember that the results won't be that great, because the IR cut filter at the sensor is blocking out just about everything but visible light and the IR pass filter that you are using at the aperture of your camera is blocking out all light but infrared. What you are left with is any IR bleedthrough that makes it through during the long exposure. This method also wreaks havoc with your camera’s autofocus system, so results will vary.
At this point, I should discuss the piece that is
the heart of any good digital IR photography setup. The
IR pass filter. This filter is placed over the aperture
of the camera either by screwing into the threads of the
barrel, or by means of a special adapter placed over the
aperture. There are two types of IR pass filter that can
be used, commercial and homemade. Commercial filters,
made by Hoya, X-Nite, Wratten, and Corkin are the best
and most durable. All of these manufacturers produce
filters at various peak sensitivities, ensuring you
capture the peak wavelength you are looking for. The Hoya
R-72, for example, only passes wavelengths above 700 -
720 nm and is a good all-around performer. The Hoya R-72
is very popular with IR enthusiasts, and is a good
starting point. You can usually pick one up for about
fifty dollars online, depending on the thread diameter of
your camera. You can also augment your setup with other
filters at higher wavelengths to experiment and see which
ones work best for different environments. If you don't
want to shell out the dough for an IR pass filter made of
glass, you can get a gel sheet (Wratten 89b) and cut it
to fit. The cost for this alternative is substantially
cheaper. Another thing to consider if purchasing a filter
for your camera is that if you have other IR capable
cameras that you wish to use it with, it needs to match
the thread diameter of the other cameras, or you will
need to purchase adapter rings to fit your other cameras.
Commercially available filters may be too expensive for someone who wishes to merely experiment with IR photography. Innovative folks have discovered homemade solutions which work very well and can be used in the same fashion. In the homemade IR filter world, there are two ways to go: floppy disk material and exposed film. Since many camera apertures are larger than the biggest single piece of collective material with either film or floppy disk material, what you would want to do with these (if you can) is cut the pieces to fit over the sensor itself and not the aperture of the camera. The first method, floppy disk material, is just as simple as it sounds. Take a 3.5 floppy disk (they are getting kind of rare, though) and open the case. Take out the disk and cut a piece of the dark disk material till you have enough to cover either the aperture of the camera (easy enough for smaller point-and-shoots) or the sensor.
The second homemade method, and also my favorite, is the exposed film negative method. Here you will take a piece of 35mm film negative that has been exposed and processed (by exposed, I mean only to light, not to pictures). An example of this is the part of the film that is exposed when you load the film canister into the camera.
If you don't have any negatives with black portions
still lying around the house, you can make your own.
Simply purchase a canister of 24 exp. 35mm film from your
local Wal-Mart or Walgreen's. Take and open the package,
pull out about 4 or 5 inches of film, and wind it back
into the film canister. Take it to the developer, and get
it developed. Explain to them that you are aware that
there are not any pictures on the film, so you do not
need any prints. Explain to them that you only need the
processed negatives. You may get some funny looks, but
you can explain if you wish that you are using the
exposed negative filter to make an infrared filter. They
might even give you some trimmed black pieces from the
beginning of other rolls that have been developed. At any
rate, simply cut two pieces of the same size to place
over either the aperture or the sensor. The double piece
of film filter method will transmit less than three
percent of visible light below 600 nm. This method is my
favorite and makes a very effective homemade infrared
filter.
A few considerations for the application of both commercial and homemade IR pass filters.
1.) When making a homemade filter (film or floppy disk material) for the aperture of the camera, make sure that you construct a housing that allows no light leakage. Stray light will ruin your pictures.
2.) When constructing a homemade filter housing to go over the expanding focus tubes of modern point- and-shoot digital cameras, make sure that it does not fit too snugly over the tube. If it binds, it can destroy the focusing motor and you will be left with a camera that will only serve as a paperweight.
3.) When using a commercial or homemade filter with a camera supporting the Niteshot™ feature, remember to use either a polarizing filter or neutral-density filter in addition to the IR pass filter. Remember with the restricted camera settings of the Sony Niteshot™ mode, it is designed only to be used a night. Daylight use can damage the system unless you take it down a few F-stops with the use of polarized or neutral density filters. This is the best system for non-modified IR setups and it is not permanent since you can still use your Sony in normal shooting modes. I have the DSC-V1 used in this configuration and I love it.
4.) Remember that if you choose one filter with a thread diameter for a specific camera and you want to use it with another camera that has a different barrel thread diameter; you will need to buy the appropriate adapter rings.
5.) Optically, homemade filters never match the clarity of a commercially available filter.
6.) If shooting at night, you will still need a strong IR light source.
7.) Finally, despite what you may read elsewhere, you do not need a separate IR filter for the flash of your camera. The aperture filter will filter out any visible light components of your flash. Odds are that it won't work anyway, as you will need a strong light source for the autofocus system to work anyway.
So if you want to try your hand at digital infrared photography, you can either modify the camera with good results, use a Sony camera with Niteshot™ and a good IR filter (and neutral density filter for daylight) for a turn-key solution, or use the brute force method and pray for good results. Personally I like the Sony solution, offers the best in autofocus and clarity. I did promise earlier that I would include information for a camera that was very easy to modify and would produce great results. The camera is the AIPTEK DV-4100M (available for 19.00 on AIPTEK.COM). It utilized a compact flash card and is capable of still photography and video shorts. The camera isn't exactly cutting edge technology, but it is highly IR sensitive and makes it a great (and easily affordable) candidate for modification. I learned of this modification at www.deadscience.com (vidcast #49) and owe Rob Fitzgerald my gratitude for posting this information. Basically you will need one piece of exposed film (not two as mentioned above, one works fine for this camera) and a little bit of patience. You will disassemble the camera, remove a sticker containing the IR cut filter, and replace it with the exposed film filter material. Reassemble and you are good to go. I also put together a blog with photos and step-by-step sequence for doing this mod. It can be found at
http://blogs.myspace.com/index.cfm?fuseaction=blog.view&friendId=405441717&blogId=475779825
What is so special about this spectrum of light? Aside from the fact that we can't see it with our naked eyes (actually, dark-adapted eyes can detect near IR at the lower end of the spectrum) it is often thought that spirits can use this spectrum of light to manifest. Perhaps this mentality was borne from the famous infrared photo of "John" (or Johann, depending on source) the supposed playful spirit that reportedly haunted the Toys-R-Us store in Sunnyvale Ca. The case received a lot of publicity and controversy in the late seventies, but one thing that came from the case was a grainy black-and-white infrared photo showing a figure leaning against a shelf. Witnesses described this figure as the ghost of "John" leaning against an aisle rack and they reported the figure wasn’t visible when the picture was taken. Another popular infrared photo was taken at the famous Bachelor's Grove cemetery in Midlothian IL. The photo, a black-and-white IR shot, depicts a woman sitting on a bench in a white flowing gown. The picture was taken during the daylight and witnesses again reported no one present in the shot while it was taken. This shot is commonly referred to as the "Madonna of Bachelor's Grove".
There are limitations to the Sony Niteshot™ systems that need to be taken into consideration. Despite the fact that their picture quality was far superior to the night vision scope method, their sensitivity to total darkness without some form of infrared illumination was abysmal. These systems required ambient light, in the form of infrared illuminators, to function in 0 lux. Sony addressed this shortcoming with the SuperNiteshot™ feature where the image was brightened by extended exposure. The problem with using this feature in any type of video is that fast moving objects created ghosting artifacts, and usually normally benign looking objects such as bugs or dust took on a Spielberg-like poltergeist visual effect. Sony also introduced the Niteshot™ feature into several models of digital point-and-shoot cameras, allowing for infrared photography. These can also be used for daylight IR photography, but more on this later.
Fast forward a few years and you find that digital photography has revolutionized the way people photograph and document paranormal research. One unexpected side effect of the digital revolution was that the CCD and CMOS image sensors were highly sensitive to the IR range (and ultraviolet as well). Manufacturers noted that this would saturate their images, so they placed a piece of glass coated with a special optic film known as an IR cut filter. Basically it allowed only visible light wavelengths to pass through to the image sensor. This cut filter would stabilize color levels in visible light, but basically makes infrared photography all but impossible. In Sony Niteshot™ products, this filter (sometimes referred to as a hot mirror) is removed from the image sensor and the color values are dropped in favor of that green hue (green is used in most night vision applications because the human eye can distinguish more shades of green in low light than any other color). Early adopters of Sony products also found that with longer exposures and a good infrared filter, certain materials of clothing became transparent in infrared. Afraid of what that would mean for Sony's liability when these cameras were used improperly, the company restricted the camera's aperture and exposure settings when in Niteshot™ mode via firmware. With the new camera settings in effect, Niteshot™ mode restricted the user to only taking pictures at night.
With digital cameras, you basically have two methods available to conduct IR photography. Removing the IR cut filter above is the most effective method, producing the best results. Another method is what I like to call the "brute force method". Most all digital cameras are so IR sensitive that there is a little IR bleedthrough even when the cut filter is still in place. You can easily test this by holding up a television remote control to the lens of the camera and pressing a button. If the infrared emitter on the remote control sufficiently lights up in a strobe light pattern, you should be able to use the brute force method with your camera. Basically, with the brute force method, you will place your infrared filter on the outside of the lens and setup the camera for a long-exposure shot. This means that you will have to use a tripod, and this is not optional. With the long exposure shot, you will undoubtedly have to experiment with ISO settings (less ISO, less grainy) and white balance settings (tungsten works best for me). Take the photo trying your best not to nudge the camera when you press the button. A remote is especially helpful here, but if one is not readily available, you may wish to use the timer function on your camera to make sure that you don't touch or vibrate the camera during the exposure. Your photos using this method will be dark, and color shifted. The color channels have no meaning in the IR spectrum, so most will oversaturate with false color. Just desaturate and change to black and white. This is the hardest and least rewarding method of infrared photography, and my least favorite. Remember that the results won't be that great, because the IR cut filter at the sensor is blocking out just about everything but visible light and the IR pass filter that you are using at the aperture of your camera is blocking out all light but infrared. What you are left with is any IR bleedthrough that makes it through during the long exposure. This method also wreaks havoc with your camera’s autofocus system, so results will vary.
Commercially available filters may be too expensive for someone who wishes to merely experiment with IR photography. Innovative folks have discovered homemade solutions which work very well and can be used in the same fashion. In the homemade IR filter world, there are two ways to go: floppy disk material and exposed film. Since many camera apertures are larger than the biggest single piece of collective material with either film or floppy disk material, what you would want to do with these (if you can) is cut the pieces to fit over the sensor itself and not the aperture of the camera. The first method, floppy disk material, is just as simple as it sounds. Take a 3.5 floppy disk (they are getting kind of rare, though) and open the case. Take out the disk and cut a piece of the dark disk material till you have enough to cover either the aperture of the camera (easy enough for smaller point-and-shoots) or the sensor.
The second homemade method, and also my favorite, is the exposed film negative method. Here you will take a piece of 35mm film negative that has been exposed and processed (by exposed, I mean only to light, not to pictures). An example of this is the part of the film that is exposed when you load the film canister into the camera.
A few considerations for the application of both commercial and homemade IR pass filters.
1.) When making a homemade filter (film or floppy disk material) for the aperture of the camera, make sure that you construct a housing that allows no light leakage. Stray light will ruin your pictures.
2.) When constructing a homemade filter housing to go over the expanding focus tubes of modern point- and-shoot digital cameras, make sure that it does not fit too snugly over the tube. If it binds, it can destroy the focusing motor and you will be left with a camera that will only serve as a paperweight.
3.) When using a commercial or homemade filter with a camera supporting the Niteshot™ feature, remember to use either a polarizing filter or neutral-density filter in addition to the IR pass filter. Remember with the restricted camera settings of the Sony Niteshot™ mode, it is designed only to be used a night. Daylight use can damage the system unless you take it down a few F-stops with the use of polarized or neutral density filters. This is the best system for non-modified IR setups and it is not permanent since you can still use your Sony in normal shooting modes. I have the DSC-V1 used in this configuration and I love it.
4.) Remember that if you choose one filter with a thread diameter for a specific camera and you want to use it with another camera that has a different barrel thread diameter; you will need to buy the appropriate adapter rings.
5.) Optically, homemade filters never match the clarity of a commercially available filter.
6.) If shooting at night, you will still need a strong IR light source.
7.) Finally, despite what you may read elsewhere, you do not need a separate IR filter for the flash of your camera. The aperture filter will filter out any visible light components of your flash. Odds are that it won't work anyway, as you will need a strong light source for the autofocus system to work anyway.
So if you want to try your hand at digital infrared photography, you can either modify the camera with good results, use a Sony camera with Niteshot™ and a good IR filter (and neutral density filter for daylight) for a turn-key solution, or use the brute force method and pray for good results. Personally I like the Sony solution, offers the best in autofocus and clarity. I did promise earlier that I would include information for a camera that was very easy to modify and would produce great results. The camera is the AIPTEK DV-4100M (available for 19.00 on AIPTEK.COM). It utilized a compact flash card and is capable of still photography and video shorts. The camera isn't exactly cutting edge technology, but it is highly IR sensitive and makes it a great (and easily affordable) candidate for modification. I learned of this modification at www.deadscience.com (vidcast #49) and owe Rob Fitzgerald my gratitude for posting this information. Basically you will need one piece of exposed film (not two as mentioned above, one works fine for this camera) and a little bit of patience. You will disassemble the camera, remove a sticker containing the IR cut filter, and replace it with the exposed film filter material. Reassemble and you are good to go. I also put together a blog with photos and step-by-step sequence for doing this mod. It can be found at
http://blogs.myspace.com/index.cfm?fuseaction=blog.view&friendId=405441717&blogId=475779825
**Photographs used in this article are the author's IR pictures from the RMS Queen Mary. For more of his IR photography, visit his FLICKR PAGE
Here are some internet resources for infrared digital
photography:
General IR Photography:
http://dpfwiw.com/ir.htm
http://infrareddreams.com/how_to_shoot_ir.htm
http://www.paranormalghost.com/ghost_tech.htm
http://en.wikipedia.org/wiki/IR_photography
http://www.wrotniak.net/photo/infrared/
http://www.echeng.com/photo/infrared/
http://www.apogeephoto.com/may2003/odell52003.shtml
http://diglloyd.com/diglloyd/free/Infrared/
Homemade Filters:
http://www.instructables.com/id/A-better-diy-infrared-filter---Take-stunning-digit/
http://www.photoaxe.com/how-to-make-your-own-photography-filters/
http://www.flickr.com/photos/atilabezdan/309061935/
http://www.diyphotography.net/take_infrared_pictures_with_digital_camera_ir_filter
Commercial Filter Comparisons:
http://homepage.mac.com/scho/MySlideshow/filtercomp.html
http://www.beyondvisible.com/BV3-filter.html
http://www.photographyreview.com/cat/lenses/filters/hoya/PRD_143242_3133crx.aspx
http://diglloyd.com/diglloyd/free/CoastalOptics60f4/spectral.html
As applied to paranormal:
http://www.ustream.tv/channel/deadscience2
http://www.lowcountryparanormal.com/index.php?/lowpar/site_pages/daylight_infrared_photography/
http://www.ghostsrus.com/Scotts%20Infared.html
Some famous (or infamous) IR ghost photos:
http://www.graveyards.com/IL/Cook/bachelors/ghost.html
General IR Photography:
http://dpfwiw.com/ir.htm
http://infrareddreams.com/how_to_shoot_ir.htm
http://www.paranormalghost.com/ghost_tech.htm
http://en.wikipedia.org/wiki/IR_photography
http://www.wrotniak.net/photo/infrared/
http://www.echeng.com/photo/infrared/
http://www.apogeephoto.com/may2003/odell52003.shtml
http://diglloyd.com/diglloyd/free/Infrared/
Homemade Filters:
http://www.instructables.com/id/A-better-diy-infrared-filter---Take-stunning-digit/
http://www.photoaxe.com/how-to-make-your-own-photography-filters/
http://www.flickr.com/photos/atilabezdan/309061935/
http://www.diyphotography.net/take_infrared_pictures_with_digital_camera_ir_filter
Commercial Filter Comparisons:
http://homepage.mac.com/scho/MySlideshow/filtercomp.html
http://www.beyondvisible.com/BV3-filter.html
http://www.photographyreview.com/cat/lenses/filters/hoya/PRD_143242_3133crx.aspx
http://diglloyd.com/diglloyd/free/CoastalOptics60f4/spectral.html
As applied to paranormal:
http://www.ustream.tv/channel/deadscience2
http://www.lowcountryparanormal.com/index.php?/lowpar/site_pages/daylight_infrared_photography/
http://www.ghostsrus.com/Scotts%20Infared.html
Some famous (or infamous) IR ghost photos:
http://www.graveyards.com/IL/Cook/bachelors/ghost.html