CY lenses tend to transmit reds and greens very efficiently. It was fairly common on my Canon 5D2 to totally saturate those colors with CY lenses, when shooting the exact same subject in the same light with Canon lenses resulted in middle intensity reds and greens. Note that this was not a color shift (white balance) issue that you can sometimes get from old lenses. This was a color intensity difference.
The ZE/ZF line trended to having this increased intensity in more the blue-green range. Taking an image from my 35/1.4 of the ocean gives vibrant blue-green, while many other lenses in the same scene would look noticeably less saturated.
My Sony Zeiss 50/1.4 had very saturated colors generally, such that my default Lightroom workflow was to reduce saturation by 5. I now have the GM but often miss the drawing of the ZA.
I have used many Zeiss lenses and have liked or loved most of them, but the color saturation they bring is among the least important reasons to me for any of that, as replicating that component of “the look” was as simple as moving the global (or a specific color’s) saturation.
Instead, what is most unique about them to me is the clarity / microcontrast / [ the dreaded ] 3D look to the images in even moderately interesting light. You can get their with other glass, but more planets have to align for it to happen.
I will never sell my Contax 100/2 for this reason, and I have repurchased the ZE/ZF 35/1.4 twice, the ZE/ZF 50/2 once. All three are just phenomenal lenses.
