I have one of those infiray T2 phone camera thermals from nightvision.co.nz. It was $750 so a way cheaper alternative to the usual monoculars. I am super impressed with it. I can see rabbits out to a few hundred meters no problems (haven't really tried further than that). I can see deer and pigs out to 1km away no problem. Several people who have looked at it have commented that the image quality is not drastically different to the expensive monoculars. It is a bit more annoying having it on the phone rather than on a handheld monocular though. It is a pain not having an inbuilt range finder like some of them have. Makes sneaking up on deer harder as not much of a idea how close you are to them before you light them up with the spotlight although that would probably get easier with more experience and if you knew the area well.
It comes with stuff so you can actually set it up as a rifle scope (clipped onto a scope rail) you would just have to mount your phone to the gun too. I think it would probably work quite well, although I haven't tried it.
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