They both must be pretty similar/same in there Lumen power output, if they both illuminate project downrange same for your image. if that the case then it nothing strange.
I dont know if the DNT digital sensor is more sensitive to favor 850nm or a 940nm ? one of them might do better Illum. than the other.
Does one flashlight use 850nm 0r 940 IR LED ? , and the other flashlight is Red IR LED 'eye visible' like 650 to 700 nm ?
do either, or both of them have collimated adjustment ? tighter beam, or both flood beam.
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