Originally Posted By: Catdog1Originally Posted By: Bowhntr6ptOriginally Posted By: Catdog1One thing I feel everyone needs to consider is... you are looking at thermal heat waves from an object. Heat detection is much slower than light transmission. Honestly to have a shift of 1-2" is not a dramatic thing. One has to remember these units are not benchrest optics set at 36x....these are thernal heat processing computers mounted to a firearm and shot.
As the image from a heat source is making its way to the scope to be processed, several things can happen to that heat signature. First off, like Mirage moves when it is blown by the wind, so does heat. Also one has to take in consideration the heat from the ground can effect the view of the target. Also weather and humidity conditions play a huge huge role.
Ideally your scope zero should be checked and adjusted on the same exact night you plan on hunting. But most people sight their scope in during the daytime under a complete different set of weather parameters than they will be hunting in at night.
I dont believe the scopes are having as much of a mounting problem casuing this as much as it is the "apperance of the target" to be in the same spot when its not.
For instance, PRS shooters know that as the sun rises and heat builds up that the target will actually be in a different location than where it appears in the scope. And if you dont know this or know how to correct for it, you will miss.
Keep in mind youre not seeing a light image of the target, youre seeing a "heat processed" image of the target. Where that taget actually is compared to where ur scope says it is could be different, and rightly so. Thermal scopes are a whole different ball game and in return we must think of them differently than day (light gathering) scopes.
What you're suggesting sounds good in theory, and per se, would be an absolute... if it were as you suggest, EVERYONE with a thermal would be experiencing this issue, and everyone is not. Some of us are having shifts whereas others are not.
If the heat waves were being "blown by the wind" on their way to the unit, we would not have the good groups we are getting now would we?
No... I'm highly suspicious there's something going on not related to your suggestion. Maybe I'm ignorant to the issue overall but are other thermal brands having the same continuous problems? Are they not using the same general technology?
All I've read about is Pulsar units causing the aggravation of shifting zeros.
ETA- I've shot in the hot FL and GA sun in the middle of the summer, well past 1K yards, and although mirage was something to contend with, I've never heard of this thing about targets being in a different spot than what I see in my scope... because I hit... just saying... so that doesn't wash with me. I'm no national PRS champion but I know my way around a long gun and distance shooting.
https://loadoutroom.com/thearmsguide/long-range-shooting-external-ballistics-light-effects/
Here's a link to one article about this there's also a couple videos on YouTube I'll try to find those tomorrow and see if I can post them for you
The article is basically useless IMO for my shooting... he says he can't quantify vertical change and says horizontal effect is perhaps 1/2" at 100 yards... Mirage is a combination of wind, heat, and light... that's nothing new.
Sorry to sound argumentative but I've shot in bright light, low light, and everything in-between and just have not observed this. Of course I'm a utility shooter and not a bench rest type guy so what do I know.
I've been to a few classes schooled by competent military and LE snipers and the instruction never included such info. While it may be true in scientific application, it's actual effect is debatable.
Again, if what you're suggesting reference thermal heat and image transfer/processing is applicable, how come EVERY thermal user is not having the same issue?