You're welcome. Yeah, IR filters can be a bit pricey but the results are very rewarding. Regarding the Hoya R72, based on my experience with the results on a Canon 400d are not as favorable as those on a Nikon D70. This is because the Canon 400d's sensor has an extra filter built into it that keeps IR light out. You can still take an IR image with it, but the exposure isn't that great. There are risky modifications available to remove the filter but i dont recommend those. If you want to test your cameras infrared ability you can try this
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