I recently started my journey into Infrared Photography. Most of my fellow photographers will know what that means. But, for my friends and followers that do not, here is a simple explanation. The sensor in the camera, the one that contains the collection of megapixels upon which the image is recorded, is covered by a filter that allows it to only record light in the frequency range we can see. Infrared cameras can record a broader range of frequencies by including heat radiation. Think of the wildlife documentaries that get those cool night shots of exotic animals. The broader range of frequencies creates some very interesting pictures. So, I am excited to begin this journey.
From this point forward, the discussion is more geared to photographers and includes some technical discussion which I will try to simplify.
My goal was to get some interesting landscapes but also to see if I could get better low light images of birds. I chose to convert my Fuji XT-3 mirrorless camera. I chose LifePixel Infrared to do the conversion. I chose the XT-3 because it has faster focusing speed than the XT-2 I had also considered.
I spent a fair amount of time determining which infrared filter to choose. Our eyes and our digital camera sensors can see frequencies between 380nm and 750nm. Below 380nm, you get ultraviolet while above 750nm you get into infrared. I did not want to get a filter that restricted me to black & white. I do not do much black & white and I can always do a black & white conversion in post processing. Looking at the choices and having no prior experience, I discussed my objectives with the support group at LifePixel and settled on their Super Color filter, a 590nm filter. That allows me to get infrared plus some visible light. By the way, you can buy an infrared filter to mount on a standard lens but, to block visible light, they are very, very dark; might be good for an eclipse.
I failed to research some other pre-conversion considerations, one of which caught me by surprise.
The biggest surprise was lens considerations. I shot my first images with XF18-55MM lens and got a hot spot in the center of the lens. I found that I also got hot spots with my XF80MM and XF100-400MM. My XF55-200MM lens works well. The hot spot on the XF100MM-400MM lens and 1.4X Teleconverter is faint and disappears in foliage, so I might be able to make it work. It also appears to get fainter at F11 and F16 so that will be subject to test. Despite not researching that, I can still do landscapes and probably do birds in the forest canopy. There are places, like LifePixel’s website that lists lenses, by manufacturer, that produce hot spots.
I dodged the bullet on focus considerations because I have a mirrorless camera. Infrared light has longer wavelengths, e.g. it includes wave lengths above 750nm. DSLR’s autofocus ability is limited to the visible spectrum, so you need to manually focus. Mirrorless cameras rely on the sensor itself for focusing as well as the rest of the capture process. So, it adapts to the infrared frequency.
The final surprise was not explained anywhere that I saw. After the conversion, I was locked out of the ability to create camera raw files. I don’t know if this is exclusive to Fuji proprietary raw files or is true across the board. It produces only JPEG. I set my camera to produce the largest JPEG it will produce.
In my next installment, I will discuss what I am learning about post-processing. Spoiler alert: white balance is critical. Infrared light is very warm.
Information Sources
- Digital Camera World, Article by Phil Hall, March 17,2020: https://www.digitalcameraworld.com/buying-guides/best-infrared-filter
- LifePixel Infrared Website, Getting Started Section: https://www.lifepixel.com/introduction
- Robert Riser, The Infrared Photography Tutorial: A Guideline for Your Ideal IR Solution: https://robertreiser.photography/infrared-photography-tutorial/
Earthwatcher 