4-16 atacr, parallax forgiveness is incredible.
This is how I define parallax forgiveness - being able to set your scope around 500 yards and have parallax free sight picture at both near and far. I found the Steiner T6Xi to be about as forgiving as the ATACR in these tests with both showing a slight bit of wobble at the closer targets.
Xtr III 3.3-18 seems a couple hundred yards of forgiveness on parallax, depending on distance. Where does the t6xi 3-18 land here?
When both ATACR and T6Xi set around 500ish on parallax, 1000 yards was virtually parallax free and up to 300ish yards was within reason with slight wobble depending on eye position, anything closer was more pronounced wobble based on eye position which could affect accuracy to the point that you would want to adjust your parallax IMO.
Low light performance isn't that good on the atacr, it gets dark quick and it seems like it tightens they eyebox(expected). The xtr isn't bad, but they both get a good amount of glare in the sunset. How does the t6xi perform there?
The ATACR struggles a bit with flare/halation above 10x whereas the Steiner handles it very well, picking up no noticeable flare, maybe some slight ghosting at 15x depending on eye position with some more pronounced at 18x but not bad by any means, this was done with the sun reflecting directly off the front objective while looking at distant objects. Depending on eye position I could induce whiteout charateristics with the ATACR from 12-16x whereas I could not induce the same with the T6Xi.
Overall the ATACR has the "better" image, hard to quantify but I'd say the T6Xi is not as contrasty which doesn't give it quite the "pop" the ATACR has, it's not terrible and one wouldn't notice if they weren't looking side by side most likely. Where the T6Xi excels is with FOV, at the same magnification the T6Xi was considerably wider than the ATACR, so with both set at 12x for example, you're going to see a lot more with the T6Xi than you would with the ATACR. Eyebox is also very forgiving with the T6Xi, moreso than the ATACR for sure, only at the very top magnification of 18x did I feel like the T6Xi was getting a bit tight. Low light, this is interesting, I expected the 56mm T6Xi to do noticeably better than the 42mm ATACR but that was not the case (to my eyes), yes it was a bit brighter but not as much as I was hoping would be the case. I need to do some further evaluations here to get a better feel for what I'm seeing (or not seeing) and may throw another 56mm scope and a 50mm scope just for comparison.
One last thing to keep in mind (not just for you zer0zero but to the community at large), these observations are for the ATACR 4-16x42 and the T6Xi 3-18x56 only, please do not use my findings for these specific scopes to make judgments about other ATACR or T6Xi scopes as each has it's own unique optical formula which can affect any of the findings here in either a negative or positive manner.
Thanks for your time.
Eta
Thanks for your review on the xtr III and your in depth on diopter adjustments, both have been a major help.
