Infrared photography is the photographing of infrared light – past the range of human vision. This makes it a very interesting and sometimes trying type of photography, as the human eye can’t actually see the final shot before it is captured by the camera. Infrared photography captures light that is faster than you or I can see – light with wavelengths of roughly 715nm (nanometers) long and higher – which produces ethereal images and ghostly pictures.
The tricky part is getting the pictures themselves – this part of the post will deal with getting the correct image onto your camera, and Roman’s post will deal with how to post process and finalize the images. Getting infrared (IR) images is hard work because digital cameras are specifically designed to block IR light, so that the captured shot is as close to real life as possible. There is an IR-blocking filter right in front of the processor that sometimes also acts as a dust shield. This brings me to the first way of obtaining IR pictures – removing the filter.
Removing the infrared filter on your camera will render the camera basically useless for anything other than IR shots. The filter can be removed DIY style, but doing this risks your camera because you have to tinker with the processor – one wrong move and you are stuck with a broken hunk of plastic. So, I would recommend getting a professional to do the conversion if you so choose to follow this method. You might be thinking, “who would do this? Why waste a camera?” Well, the simple answer is that without converting the camera you will constantly be fighting the filter inside your camera with another filter which means a lot of blocked light. Low amounts of light entering your camera means long exposure times; and I mean long. So, if you convert your camera, you get to enjoy relatively normal exposure times and the benefit of seeing through your viewfinder. Lucky you.
The other option – a more temporary, non-permanent solution – is to get an infrared filter. There are many out there ranging from roughly $50-$100, the one I chose was the Hoya R72 (a very common IR filter that blocks out all light under 720nm long) Think about what that means though: MOST OF YOUR visible spectrum of LIGHT IS BLOCKED OUT. You will see nothing through the viewfinder, because not enough light can get in (sometimes live view will work however, which is great for getting the focus dead-on). You will need exposures in the day time of 10 seconds or longer, you will need a tripod, and you will need to set custom white balances. The following guide will give information about using IR filters.
Step 1: WHITE BALANCE
This is the most irksome part of infrared photography. Without properly setting the white balance, you will not get white foliage or interesting shadows. You will get the color of the filter, be that red, or brown, or whatever.
There are a few ways around this. The one I find the most effective is to use the custom white balance and to get a sample shot for your camera to use. The end goal is to get completely white trees, grass, and shrubs and all that whatnot. To do so, set the white balance to sunny, put the filter on, find an all green patch of grass, or whatever it may be, in sunlight, focus (tips on that in a bit), set exposures, and shoot. Then, go to your preset white balance menus and set the picture you just took as the new white balance.
Your pictures should now come out with the correct white balance and will look something in the area of this (tones may vary by filter brand, but most foliage should be basically white because of the infrared light reflecting off of them). Note that this is not a final product, and still needs work in photoshop.
Step 2: COMPOSING THE SHOT
How do you compose through a black viewfinder? Hmm? Well, I’ll tell you. Use the live view feature on your camera (if like Roman you are lucky enough to have one ) to see a redish, darker version of the scene, or compose the shot without the IR filter on and then attach the filter… that’s about it.
Step 3: FOCUSING
Focusing of course has to be difficult and troublesome just like every other part of IR photography, but I swear it is worth it in the end! The gist of the situation is that IR light has a different focal length than normal light, so even if your camera had enough light getting in the lens (which it doesn’t when the filter is on) the auto focus would be wrong. When working in IR, you need to focus a bit closer than normal. Now you have another problem on your hands, you have to focus on something you can’t see (live view sometimes can help you here). My solution is to compose the shot, auto focus, attach the IR filter, focus in a tad CLOSER, work where your lens has the highest DOF (typically f/8). How much closer you will have to focus depends on how far the object is away from you, so it’s sort of a guess and check type of deal – just work in small increments. After a while, the focus should be tolerable. Just for quick reference, my method again is to:
1. Use AF with the shot composed and the filter off
2. Put on the IR filter
3. Switch to manual focus
4. Focus a bit closer
5. Take the shot and repeat until happy
Step 4: EXPOSING
Most light is being blocked from your camera, so exposure times are through the roof. You absolutely need to use a stable tripod. Assuming you are using the aperture most suitable for a high DOF and clarity, even less light is being let in. For example, when working with F/8 with an ISO of 200 it took 25 seconds to expose the white balance example picture – which was shot at around 3:30 pm with the sun right above the horizon behind me (direct sunlight). I recommend using an ISO of under 400 to keep the noise-sensitive whites clean. Again, experimentation is the best solution here.
Step 5: POST PROCESSING
Open Photoshop, and follow this tutorial.
Good luck! Please comment if you have any questions or need any help!