Hi Leon
My take on this is if you replace the uv/ir cutoff filter with clear glass or no filter at all then the camera will be sensitive to near and far infrared as well as uv. This would imply then that your dso pics would show all kinds of responses to these wavelengths.
From my understanding the astronomical value of these filters is up to about 700 to 800 nm as this will allow Ha through but not IR due to heat etc.
Hutech classify their filters as astronomy and Infra red.
Infra red is useful for heat source detection.
