While assuming Full Frame Format to be 36mm Wide and 24mm High of a Sensor Area ( which is not 100% accurate, cause different Camera brands use slightly smaller or Larger Sensors, but its usually close enough) and the Chronos 1.4 having a Sensor size of 8,45mm Wide by 6,76mm High at full Resolution; the Horizontal Crop factor compared to FullFrame would as a Result be 4,26x.
In the 1.4 Manual the Crop Factor is Quoted as 3,9x, but this isnt really accurate if the 1.4 is used to shoot 16:9 Format Footage (the Quoted Crop factor is refering to Diagonal Field of View, which of course is technically correct, but wont apply unless you use the Full Width as well as Height of the Sensor, therefore Horizontal Crop Factor is more accurate in this Case)
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Meaning your Tokina Lens zoomed out would end up being a Equivalent Focal Length of 46,86mm when Converted to FullFrame Equivalent.
For anything really worth calling a Wide Angle Lens on the Chronos 1.4; you would want to have a Lens with 8 to 6mm Focal Length or even wider, especially if you use smaller Resolutions (which will Crop the Sensor even further....).
For Focal Length that short, you will usually have a Hard Time finding appropriate Lenses For EF-Mount, using C-Mount or MFT-Mount Lenses is likely the only thing that makes sense.
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If you got some Special Focal length in mind you are Looking for, i can try to see if i can find any good ones.