Which upgraded IR do you have, the 850 Pro? I do not have the ATN, I have the Sightmark and mine will illuminate up to 150yds, but my version has the 940nm IR. The 850nm are supposed to reach 300 yards, but not sure if that is a clear picture at 300 to know what you are seeing. I am curious if others have any experience with a brighter IR, what range they are able to identify targets, black hog etc and know they are looking at a hog and not a black calf.. I have thought about adding an ATN HD Smart Pro for another AR build I will do this year.
When I use the ATN at distance I remove the (baffle) small restricting hole in the objective end. I need it for close shots over bait to keep from washing out. It makes a difference on you surroundings with ir shadows.
Thermal is better.
Not sure if they are available but in the military we ran an IR lens over standard flashlight. Not sure what the price would be but I would imagine it would have to be cheaper, and then you could switch flashlights.
Been running an Armasight IR-850 illuminator with their A-focal doubler for quite a while. With doubler attached it's a bit big and bulky but significantly extends the range. The light has multiple power settings. Recently picked up a Steiner SPIR which is pricey and advertised to reach 1000 meters but ended up returning it because the Armasight IR-850 with doubler outperformed it.
I also have another set up on my 6.8 that uses an adjustable Green laser (The green laser is visible all the way to the target to aid in locating it and it does not spook the game and it does a really good job of illuminating the target at night. I have the rifle sited in with the scope, and as it turns dark I can turn the green Laser on and adjust the size of the spot for the distance necessary to fill the scope (Normally I adjust it to about 4' dia or less depending on the distance @) then just activate and look through the scope when needed and shoot.
It really works great, and you can see amazingly good. If you don't have the money to
buy a night vision scope, it is a good alternative. It is a little more expensive Than the IR 850 but $200.00+ dollars is cheaper than a night scope and the illuminator.