Everything you know about visible light is wrong when working with infrared images. Since exposure meters are not sensitive to infrared light (or even LED lighting, but that’s a subject for another day,) it can be difficult to calculate exact exposures but that doesn’t mean you shouldn’t try. Although digital camera’s LCD screens provide instant feedback, it’s not always accurate. Two subjects that seem equally bright under normal (visible) light might reflect infrared radiation at different rates and exhibit different brightness. And as I’ve discovered time of day can have a dramatic effect on the results. So what’s a poor hippo to do? (as it says on my favorite coffee mug)…
Tip #1: Bracketing, if you are not already familiar with the term, means that you make several photographs of the same scene, increasing or decreasing the exposure with each additional frame. Some digital cameras an auto bracketing function that make a specified series of shots at exposures over and under what is considered “normal.” Because every camera’s a little different, read your camera’s manual for specific directions.
Even if your camera doesn’t have bracketing function it should have an Exposure Compensation feature that lets you adjust exposures in one-half or one-third stops while shooting in automatic exposure modes. If all fails, most digital cameras offer a Manual mode. You don’t need a hand held exposure meter to get started. Typically I just look through the viewfinder in Program mode and see the suggested exposure, then transfer that shutter speed and aperture to the camera after it’s set in manual mode and then bracket on the overexposure side until I see the white foliage is clean and bright on the LCD screen
Tip #2: Just because you don’t have a converted IR camera doesn’t mean you can’t use all the tips covered here with cameras that are IR capable out of the box. It does mean that when using dark (you can’t see though them) filters you will probably need a tripod because of the long exposure times produced.
Tip #3: When using filters, focus first then put the filter on the camera. Usually I just hold it there with my fingers during the exposure or have somebody else, as Mary is doing here hold it, which is just another reason a tripod comes in handy.
If you want to save a few bucks when converting your camera to infrared when ordering a conversion from LifePixel, use the coupon code “farace.”