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The world began its love affair with infrared photography back in October, 1910 when the Royal Photographic Society published, in its journal, a collection of images by American physicist and inventor, Robert Williams Wood (1868-1955).
Wood has been described as the father of infrared photography having intentionally produced photographs from infrared radiation.
His discovery finally led to the invention of infrared sensitive film. One of its early uses was in surveillance applications due to its ability to cut through haze; aerial reconnaissance teams used it during the Second World War as a method of finding camouflaged enemy positions.
For the enthusiastic amateur photographer infrared photography has opened up a whole new world of imagery. The peculiarities of infrared photography are deep black skies, bright white foliage and that magical, sometimes eerie diffused glow.
Infrared photography has given us the ability to record what the eye cannot see. As humans our eyes are sensitive to a limited band of wavelengths, between 400nanometres (the blue spectrum) and 700 nanometres (the red spectrum) known as visible light.
Infrared light-waves on the other hand stretch beyond this red spectrum and travel on, right up to microwaves, past 10.000nm. The infrared spectrum is split into three sections; Near Infrared, Far Infrared and Thermal Infrared.
As infrared photographers it’s the near infrared spectrum that interests us the most; the ~700 – 900 nanometre range. The far infrared spectrum, above 900nm, deals mainly with heat waves, which is beyond the range of what a modern day digital camera can capture.
With a capable digital infrared camera many scenes, which under normal lighting conditions maybe considered ordinary to some, are often transformed when captured in infrared. With digital infrared there are a number of different ways in which the final image can be processed giving the photographer complete artistic control.
What type of camera will I need?
The sensors fitted in all digital cameras have the ability to capture a large portion of the electromagnetic spectrum, from the ultra-violet (400nm) right up to near Infrared (900nm). However, because infrared radiation contaminates images taken under normal “visible light” conditions all modern day digital cameras are fitted with a special infrared blocking filter, called a hot mirror or a cut filter. This filter lets in light from the ultra-violet spectrum (400nm), but blocks out light from the infrared spectrum, above 700nm.
Therefore, in order for us to capture infrared images we must reverse this process and block out all visible light below 700nm. To do this we replace the cut filter with an infrared filter. If this modification is made then any digital camera on the market will be able to take infrared images.
However, here lies the problem! The process of removing the hot mirror filter is tricky and needs to be handled by a qualified technician; otherwise you run the risk of harming yourself or damaging your camera, maybe even both!
On the other hand, all is not lost; some digital cameras are quite sensitive to infrared wavelengths even with their hot mirror filters still firmly in place. One such camera is the renowned Olympus C-2020z, a simple point and shoot digital compact camera, which has a 2.1 megapixel sensor. By placing an opaque filter, such as a Hoya R72 in front of the lens, infrared photography becomes possible. In fact, some of the best performing cameras for infrared photography have been those produced in the early days of digital photography, when digital camera manufactures were less concerned with infrared contamination.
The sensor used in the C-2020z was manufactured by Sony; this sensor was also fitted to a number of other cameras offering the same 2 megapixel capabilities, notably Sony’s own S50 and Nikon’s early Coolpix range; 700/800 and 950. All these cameras now have legendary status amongst infrared photographers and as a result are becoming quite collectable and increasingly difficult to get hold of.
If you have your sights set on something a bit more versatile, but without resorting to a full blown infrared conversion, take a look at any of the 6 megapixel Nikons; D40 D50 and D70. Although these cameras won’t allow you to make hand-held infrared exposures they are pretty much sort after as infrared sensitive cameras.
If you happen to own a Canon DSLR then I’m afraid you will have to have it fully converted to shoot infrared. The only model that is practically sensitive enough to capture infrared image without the conversion is the 3.2 megapixel D30, not to be mistaken for the later 8.2mp 30D.
At the end of the day the camera is but a tool, a means to an end.
What IR filter should I use?
If you plan on using a none-converted camera to capture infrared images the filter you choose will largely depend on your lens choice? Personally I would recommend something like a wide-angle zoom, such as an 18-70mm. This type of lens makes it practical for you to cover most subjects, from landscapes to portraits and in some cases, depending on lens construction, close ups or macro.
Not only do infrared filters come in different sizes, but they come in different strengths too. Remember, these filters are designed to block out light at different wavelengths. The weakest infrared filter you will find in the Cokin (P007) infrared filter. This filter blocks out light-waves below 650nm, but as we have already established, near infrared light starts at around 700nm, therefore, the Cokin filter will still allow a fair portion of visible light through. This is fine if you want coloured infrared, but the majority of digital infrared photographers are aiming for a more traditional look.
Nonetheless, the most popular infrared filter, by far, is made by Hoya, the R72 infrared filter. This filter will block out light-waves below 720nm. Because these filters are opaque the resulting RAW files have a reddish brown cast to them, which I will explain more about later. The reason I mention it now is because the Hoya R72 is the preferred filter for those photographers who wish to render their infrared skies blue; again, a subject I will touch upon in a moment.
If you want to capture a more traditional looking infrared image, one that is stripped entirely of colour, then you will have plump for a stronger blocking filter; above ~750nanometres.
Do I have a personally favourite? No, not really – I use all three filters on different cameras. I’ve found that certain cameras perform better to one type of filter than they do to another. For instance, I use a Hoya R72 on my Olympus C-2020 and Nikon D50, I will use a 750nm infrared filter on my Canon G9 and I canalised my old Cokin P007 filter to convert my Nikon Coolpix 995 to infrared. Three entirely different filters, but suitably matched to the cameras I use them with.
Exposure, Metering and Focusing
The downside to using any infrared filter over your lens is speed.
Because the infrared filter covering your lens is trying to block out all visible light and the internal hot mirror filter is effectively blocking out all near infrared light the amount of actual light hitting the cameras sensor is minimal. Consequently, shutter speeds times will be painfully slow. Even on a bright sunny day, working with a relatively sensitive camera, such as the Nikon D50, your shutter speeds are still going to be in the region 2 or 3 seconds at f8, with some cameras, considerably more! Obviously some kind of support is going to be needed whatever camera you use?
Some photographers might see this as a problem, others not. However, I have to mention it, this isn’t your only problem! Composition of your subject has to be made without the infrared filter in place, for the simple reason, the filter is opaque; you can't see though it.
To make your exposure you will need to fix your camera firmly to a tripod, compose your shot in the normal way and refit the infrared filter before taking your shot. This may sound simple enough, but after awhile it does become tedious and irritating. Anything other than landscapes or objects that don’t move is pretty much out of the question!
Because our camera lenses are designed to work best under normal lighting conditions and not under infrared radiation, there’s also a slight shift to your point of focus. Some older, manual focusing lenses, will have a red infrared focusing dot to compensate for this, newer ones may not. To overcome this focusing discrepancy it’s wise to stop your lens down to a small aperture thereby maximising your depth of field.
Modern day digital cameras all have very good metering systems; even the very early digital compacts were quite good. Nonetheless, when shooting in infrared the last thing you want to do is blow those highlights. For this reason I would advise you under exposure your images by at least 1/3rd of a stop.
Regardless whether your camera has been fully converted or not, to get the best possible results from your images, you will need to shoot everything in RAW; this isn’t an option, but a necessity! Why? Because RAW files contain more information, which will allow you better control over the final exposure and complete control of your white balance.
If your camera doesn’t allow for RAW captures, most digital compacts don’t, confine your images to un-compressed tiff files. Un-compressed tiffs from the Olympus C-2020, Nikon Coolpix 700/800/950 and the Coolpix 995 when processed correctly hold enough information for you to make A3 prints.
If you only ever use your camera for taking infrared images you may want to consider having the hot mirror filter completely removed and an infrared filter put in its place. The benefit of this procedure is easy to see; Normal shutter speeds, no messing around with filters, use any lens you wish, no tripod to carry around and no focusing issues to deal with.
If you only ever use your camera for taking infrared images you may want to consider having the hot mirror filter completely removed and an infrared filter put in its place. The benefit of this procedure is easy to see; Normal shutter speeds, no messing around with filters, use any lens you wish, no tripod to carry around and no focusing issues to deal with.
In the past I was quite happy to shoot with the filter screwed to the lens, but once you have used a fully converted infrared camera you won’t want to go back to using anything else.
Selecting Your White Balance Point
OK, now comes the important bit, selecting your white balance.
Whether you own a fully converted digital infrared camera or you use an infrared filter over the lens, your images will take on a colour cast. A weak infrared filter similar to the Cokin filter will produce a distinct red cast; a stronger infrared filter above 750nm will appear monochrome, which leaves the Hoya R72 type in the middle with a reddish brown cast. Before we can get our images looking anything like the infrared images taken on film, we need to get rid of the colour cast.
There is two possible methods by which this can be achieved; in camera (if your camera allows it) or with software. I will deal with in camera white balance first as this is the easiest method to explain.
Go to your cameras white balance menu, from here you can choose from Auto, Sunny, Cloudy, Incandescent, Florescent; find the option that lets you choose a “Custom” white balance.
What happens here is the camera will let you record an image under the prevailing lighting conditions you are working in.
For Example; if you happen to be taking a landscape picture choose your “Custom” white balance from a patch of grass in full sunlight, take the shot and the camera will save and store this image as your custom white balance. If the light changes at any point during the day, simply record a new white balance and save it. You will see the efforts of your white balance setting on your cameras viewing screen as you take your shots.
Alternatively, you can leave your camera’s white balance set on “Auto” and then, when you open the image in your RAW conversion software; simply choose a white balance point from there.
Not sure if it's the correct thing to do, but more information, including pictures, can be found on my infrared website:
www.in4red.co.uk
Thanks for stopping by
Wood has been described as the father of infrared photography having intentionally produced photographs from infrared radiation.
His discovery finally led to the invention of infrared sensitive film. One of its early uses was in surveillance applications due to its ability to cut through haze; aerial reconnaissance teams used it during the Second World War as a method of finding camouflaged enemy positions.
For the enthusiastic amateur photographer infrared photography has opened up a whole new world of imagery. The peculiarities of infrared photography are deep black skies, bright white foliage and that magical, sometimes eerie diffused glow.
Infrared photography has given us the ability to record what the eye cannot see. As humans our eyes are sensitive to a limited band of wavelengths, between 400nanometres (the blue spectrum) and 700 nanometres (the red spectrum) known as visible light.
Infrared light-waves on the other hand stretch beyond this red spectrum and travel on, right up to microwaves, past 10.000nm. The infrared spectrum is split into three sections; Near Infrared, Far Infrared and Thermal Infrared.
As infrared photographers it’s the near infrared spectrum that interests us the most; the ~700 – 900 nanometre range. The far infrared spectrum, above 900nm, deals mainly with heat waves, which is beyond the range of what a modern day digital camera can capture.
With a capable digital infrared camera many scenes, which under normal lighting conditions maybe considered ordinary to some, are often transformed when captured in infrared. With digital infrared there are a number of different ways in which the final image can be processed giving the photographer complete artistic control.
What type of camera will I need?
The sensors fitted in all digital cameras have the ability to capture a large portion of the electromagnetic spectrum, from the ultra-violet (400nm) right up to near Infrared (900nm). However, because infrared radiation contaminates images taken under normal “visible light” conditions all modern day digital cameras are fitted with a special infrared blocking filter, called a hot mirror or a cut filter. This filter lets in light from the ultra-violet spectrum (400nm), but blocks out light from the infrared spectrum, above 700nm.
Therefore, in order for us to capture infrared images we must reverse this process and block out all visible light below 700nm. To do this we replace the cut filter with an infrared filter. If this modification is made then any digital camera on the market will be able to take infrared images.
However, here lies the problem! The process of removing the hot mirror filter is tricky and needs to be handled by a qualified technician; otherwise you run the risk of harming yourself or damaging your camera, maybe even both!
On the other hand, all is not lost; some digital cameras are quite sensitive to infrared wavelengths even with their hot mirror filters still firmly in place. One such camera is the renowned Olympus C-2020z, a simple point and shoot digital compact camera, which has a 2.1 megapixel sensor. By placing an opaque filter, such as a Hoya R72 in front of the lens, infrared photography becomes possible. In fact, some of the best performing cameras for infrared photography have been those produced in the early days of digital photography, when digital camera manufactures were less concerned with infrared contamination.
The sensor used in the C-2020z was manufactured by Sony; this sensor was also fitted to a number of other cameras offering the same 2 megapixel capabilities, notably Sony’s own S50 and Nikon’s early Coolpix range; 700/800 and 950. All these cameras now have legendary status amongst infrared photographers and as a result are becoming quite collectable and increasingly difficult to get hold of.
If you have your sights set on something a bit more versatile, but without resorting to a full blown infrared conversion, take a look at any of the 6 megapixel Nikons; D40 D50 and D70. Although these cameras won’t allow you to make hand-held infrared exposures they are pretty much sort after as infrared sensitive cameras.
If you happen to own a Canon DSLR then I’m afraid you will have to have it fully converted to shoot infrared. The only model that is practically sensitive enough to capture infrared image without the conversion is the 3.2 megapixel D30, not to be mistaken for the later 8.2mp 30D.
At the end of the day the camera is but a tool, a means to an end.
What IR filter should I use?
If you plan on using a none-converted camera to capture infrared images the filter you choose will largely depend on your lens choice? Personally I would recommend something like a wide-angle zoom, such as an 18-70mm. This type of lens makes it practical for you to cover most subjects, from landscapes to portraits and in some cases, depending on lens construction, close ups or macro.
Not only do infrared filters come in different sizes, but they come in different strengths too. Remember, these filters are designed to block out light at different wavelengths. The weakest infrared filter you will find in the Cokin (P007) infrared filter. This filter blocks out light-waves below 650nm, but as we have already established, near infrared light starts at around 700nm, therefore, the Cokin filter will still allow a fair portion of visible light through. This is fine if you want coloured infrared, but the majority of digital infrared photographers are aiming for a more traditional look.
Nonetheless, the most popular infrared filter, by far, is made by Hoya, the R72 infrared filter. This filter will block out light-waves below 720nm. Because these filters are opaque the resulting RAW files have a reddish brown cast to them, which I will explain more about later. The reason I mention it now is because the Hoya R72 is the preferred filter for those photographers who wish to render their infrared skies blue; again, a subject I will touch upon in a moment.
If you want to capture a more traditional looking infrared image, one that is stripped entirely of colour, then you will have plump for a stronger blocking filter; above ~750nanometres.
Do I have a personally favourite? No, not really – I use all three filters on different cameras. I’ve found that certain cameras perform better to one type of filter than they do to another. For instance, I use a Hoya R72 on my Olympus C-2020 and Nikon D50, I will use a 750nm infrared filter on my Canon G9 and I canalised my old Cokin P007 filter to convert my Nikon Coolpix 995 to infrared. Three entirely different filters, but suitably matched to the cameras I use them with.
Exposure, Metering and Focusing
The downside to using any infrared filter over your lens is speed.
Because the infrared filter covering your lens is trying to block out all visible light and the internal hot mirror filter is effectively blocking out all near infrared light the amount of actual light hitting the cameras sensor is minimal. Consequently, shutter speeds times will be painfully slow. Even on a bright sunny day, working with a relatively sensitive camera, such as the Nikon D50, your shutter speeds are still going to be in the region 2 or 3 seconds at f8, with some cameras, considerably more! Obviously some kind of support is going to be needed whatever camera you use?
Some photographers might see this as a problem, others not. However, I have to mention it, this isn’t your only problem! Composition of your subject has to be made without the infrared filter in place, for the simple reason, the filter is opaque; you can't see though it.
To make your exposure you will need to fix your camera firmly to a tripod, compose your shot in the normal way and refit the infrared filter before taking your shot. This may sound simple enough, but after awhile it does become tedious and irritating. Anything other than landscapes or objects that don’t move is pretty much out of the question!
Because our camera lenses are designed to work best under normal lighting conditions and not under infrared radiation, there’s also a slight shift to your point of focus. Some older, manual focusing lenses, will have a red infrared focusing dot to compensate for this, newer ones may not. To overcome this focusing discrepancy it’s wise to stop your lens down to a small aperture thereby maximising your depth of field.
Modern day digital cameras all have very good metering systems; even the very early digital compacts were quite good. Nonetheless, when shooting in infrared the last thing you want to do is blow those highlights. For this reason I would advise you under exposure your images by at least 1/3rd of a stop.
Regardless whether your camera has been fully converted or not, to get the best possible results from your images, you will need to shoot everything in RAW; this isn’t an option, but a necessity! Why? Because RAW files contain more information, which will allow you better control over the final exposure and complete control of your white balance.
If your camera doesn’t allow for RAW captures, most digital compacts don’t, confine your images to un-compressed tiff files. Un-compressed tiffs from the Olympus C-2020, Nikon Coolpix 700/800/950 and the Coolpix 995 when processed correctly hold enough information for you to make A3 prints.
If you only ever use your camera for taking infrared images you may want to consider having the hot mirror filter completely removed and an infrared filter put in its place. The benefit of this procedure is easy to see; Normal shutter speeds, no messing around with filters, use any lens you wish, no tripod to carry around and no focusing issues to deal with.
If you only ever use your camera for taking infrared images you may want to consider having the hot mirror filter completely removed and an infrared filter put in its place. The benefit of this procedure is easy to see; Normal shutter speeds, no messing around with filters, use any lens you wish, no tripod to carry around and no focusing issues to deal with.
In the past I was quite happy to shoot with the filter screwed to the lens, but once you have used a fully converted infrared camera you won’t want to go back to using anything else.
Selecting Your White Balance Point
OK, now comes the important bit, selecting your white balance.
Whether you own a fully converted digital infrared camera or you use an infrared filter over the lens, your images will take on a colour cast. A weak infrared filter similar to the Cokin filter will produce a distinct red cast; a stronger infrared filter above 750nm will appear monochrome, which leaves the Hoya R72 type in the middle with a reddish brown cast. Before we can get our images looking anything like the infrared images taken on film, we need to get rid of the colour cast.
There is two possible methods by which this can be achieved; in camera (if your camera allows it) or with software. I will deal with in camera white balance first as this is the easiest method to explain.
Go to your cameras white balance menu, from here you can choose from Auto, Sunny, Cloudy, Incandescent, Florescent; find the option that lets you choose a “Custom” white balance.
What happens here is the camera will let you record an image under the prevailing lighting conditions you are working in.
For Example; if you happen to be taking a landscape picture choose your “Custom” white balance from a patch of grass in full sunlight, take the shot and the camera will save and store this image as your custom white balance. If the light changes at any point during the day, simply record a new white balance and save it. You will see the efforts of your white balance setting on your cameras viewing screen as you take your shots.
Alternatively, you can leave your camera’s white balance set on “Auto” and then, when you open the image in your RAW conversion software; simply choose a white balance point from there.
Not sure if it's the correct thing to do, but more information, including pictures, can be found on my infrared website:
www.in4red.co.uk
Thanks for stopping by
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