Sunny, calm day down at Bilgola beach today so I thought I’d give the infrared (IR)converted X-E1 a go. All the images are shot with the 14mm lens. I added a 10 stop Lee ND filter to get slower shutter speeds. All are around the headland between Bilgola and Newport Beaches.
The X-E1 was converted to infrared by Camera Clinic in Melbourne. They specialise in infrared conversions and are also authorised Fuji repairers.
There are essentially three options for shooting infrared:
A. Use infrared film in a film camera – not sure you can still buy it! It also had to be kept cool all the time and, of course, processing was chemical based – back to the darkroom!
B. Use an infrared filter on the lens of your camera, such as the Hoya R72. This is a cheaper option but is a slow way of working. Shutter speeds are slow, requiring a tripod and focusing needs to be done without the filter in place – as it’s too dark, usually, to see through. On top of all that your camera may not be very sensitive to infrared in the first place because it has an IR blocking filter over the sensor (most digital cameras do – though some are made without an IR blocking filter, or a modified one, for special applications e.g. Fujifilm X-T1 IR (crime investigation), Nikon D810A -really for astrophotography but has a specialized IR cut filter that captures the red tones of H-alpha emission nebulae – not really IR photography in terms of the this post. There are also industrial cameras used in manufacturing and crime scene investigation).
C. Have your camera converted to infrared. The camera’s IR blocking filter is removed and replaced with one that allows IR to pass through and blocks visible light. The wavelength of IR that can be passed can vary depending on what filter is chosen. I opted for 680 nanometres (680/1,000,000,000 (or 0.000000680 a metre). The Hoya R72 is 720 nanometres. With this option exposures are what you would expect with an unconverted camera. The references below deal with the different wavelength filters and also having ‘no filter’ – or a full spectrum conversion.
Having the right lens for IR photography is an issue. Many lenses exhibit a “hotspot” – a bright spot in the centre of the image that varies with intensity as the lens is stoped down. Lenses are made to work with visible light and the commentary I’ve read suggests that the coatings used on the lenses do not prevent flare, ghosting and internal reflections with IR light as they do for visible light. A number of the Fuji lenses have been tested here: Fuji lenses for IR. The 14mm and 23mm lenses work well. I’ve not been able to find anything that explains why, when all lenses have coatings, some do not show a hotspot. I guess it’s also a matter of the construction of the lens, in combination with the coatings.
A lot has been written about IR photography. Some specific references:
Life Pixel Infrared conversions (US based) has an extensive website about conversions, lenses and post processing etc.
Camera Clinic (Melbourne, Australia based) information on conversion, white balance settings and post processing.
Google search for Infrared photography with a digital SLR.
Google search for infrared photography with a mirror-less camera.