Post by xman on May 27, 2022 10:03:09 GMT -8
I have the ATN ThOR 4 640 2.5-25x and have enjoyed the hunting capability it provides. I've made recommendations in other threads that would improve the utility of the ThOR. Here is one that will improve its performance. I am experiencing performance degradation when the sky is taking up a large portion of the FOV, especially when the crosshairs are close to the horizon. I assume this is caused by the cold in deep space affecting the sensitivity/gains. This can be compensated in a wider FOV by placing the crosshairs well below the object of interest while following it. Two examples of this effect are below. The clarity reduction by moving the FOV higher to place the crosshairs closer to the horizon where the coyote or hog may be can be seen in the second of the two images ( -C and -D).
This becomes an issue when I zoom in to take a shot. Now the crosshairs are on the hog/coyote but the sky has fills the top half of the sensors FOV, even though my view finder's magnified image has no sky in view.
see images in post #3 below as I've reached the limit.
On the FLIR systems I've flown and integrated on Navy and Air Force fighters, we first reduced this problem by not letting thermals well above the horizon provide inputs to the auto-gain features. Then, as computing power improved, gain compensation independently accomplished in different sections of the image.
