That's interesting what you say about mirage DT. I've always thought that comes down to overall IQ and a scopes ability to resolve detail and micro contrast, so I wonder if the TT still has an "edge" over the ZCO in this regard. ILya, this might be a great topic for a video to talk about a scopes ability to "cut through" mirage, if that is even possible. I realize it could just be our eyes or our brains interpretation of what our eye is seeing.
Also, with regard to the price difference I thought the ZCO sells for $3600 and the TT sells for $4663, that is $1000 difference right or are you talking about street price and the fact that a TT can be had at less than full retail while the ZCO cannot?
Personally, I'd have a harder time with the ZC527 because of the competition from TT, Schmidt and Minox ZP5 as these scopes are peers and pretty much the same magnification, but the ZC420 really stands out above the crowd and like ILya mentioned, I'm trying to figure out a reason to pick one up. I do wish the MPCT reticles had dots in the Christmas tree like the MR4 as I am not a fan of bold tree reticles, heck I even feel the SKMR3 is bold and its thinner than the MPCT2, but for the main horizontal and vertical stadia I prefer the thicker lines of the MPCT series over SKMR. For this reason I might lean toward the MPCT1 reticle in the ZC420; however, if they had dots in the tree like the MR4 I'd definitely pick that up, maybe a future MPCT3 reticle will have dots in the Christmas tree as I'd much prefer that over the MPCT2.
Seeing through mirage is kind of a tricky topic.
I have some empirical experience with that since I find the subject interesting and I have been looking into it, but I have comparatively little fundamental knowledge on the subject.
When @covertnoob and I were looking at a bunch of 56 mm scopes for this test a while back, one thing that jumped out to both of us was that at 100 yards the differences between the better scopes were minor, but beyond 600, TT edged ahead of everyone else.
One thing that definitely makes a difference is depth of field. That is a simple experiment: set up and optic and look at a target on a hot day. Then put in an aperture reducer which increases depth of field. You will see through the mirage better if the aperture reducer is in place.
Other differences that seem to be apparent likely pertain to how we perceive images. Optics that offer a lot of subtle tonal detail (TT, Leica, etc) do well with mirage. I suspect that it just makes it easier for our eyes to process the image. Mirage washes out a lot of the color and our brain needs those details to comprehend what the eye is looking at.
At closer distances, I think ZCO outresolved TT slightly, but at longer distances, TT's color rendering and microcontrast gave it an edge.
ILya