Hi Rob, using a external filter still gives very good results, I still use a external filter if I want more dramatic IR images, as my external filter is very dark and will not allow any color through at all. But the advantage of a dedicated IR camera is that you are not restricted to long exposures, so handheld shots are normal, plus I find that I can only use a external filter on a very sunny day with no wind, otherwise foliage will move during exposure and appear blurred.

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Beacon Images - last updated 29th June