Infrared Blossoms (Sony DSC-V3)
I’ve posted previously about creating infrared images with the Sony DSC-V3 but never shown the actual contrivance that I use to do it. In an ideal world I wouldn’t need all the step rings but I’ve tried to use only what I have available to me and as the infrared filter is the most expensive item everything else must revolve around that, literally.
Starting at the camera side is what would appear to be an extraneous item a 48mm extension ring however what this does is, through having less threads than the extension tube, over ride the cameras sensor for detecting the extension tube. This allows you a limited amount of zoom which would other wise be locked at its maximum. The next thing is the extension tube itself which places the rest of the filters out of the way of the cameras lens. Ignoring the step rings the next important item is the Rodenstock RG715 filter. Within its name is a clue to its function, the 715 refers to the wavelength of light that it allows through. The RG715 blocks light bellow 715nm and passes the near infrared above this. As visible light is defined as between 390 and 750nm you can see that most of the light we see with our eyes is blocked. After the IR filter I use neutral density filters to cut down the total amount of light coming in. When the camera is in “Night Shot” mode in daylight the sensor is overwhelmed and the image is completely washed out. This happens because the camera locks out all user adjustment in this mode forcing the shutter speed to 1/30sec and bellow.
And of course the camera itself needs to be set to Night Shot mode. What happens in this case is the camera flips it’s small internal infrared filter out of the way allowing those higher wavelengths of light to fall on the sensor. Normally this extra light would be unwanted and be detrimental to the image but this is the light I am after. The results are mixed, yes you get a near infrared image but the overall image quality is lower than the camera can produce in normal operation and without being able to control the exposure that too can be hit and miss. I’m not aware of any current cameras that have provisions for IR photography without actually modifying the camera but a modified DSLR would give better results for sure.
