Quantize panel tuplets

Does anyone know how this works? I played 7-tuplets and accuracy is a little off as can be seen in the distances between them. I set the quantize panel for 7 in the time of a half note (2 quarters). If I apply with those 7 selected, the 1st note disappears, and the others move closer to the beat 4 while looking equally spaced.


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Alternatively, how many ticks are there in a quarter note, so I could divide the sum of 2 by 7 and apply the spacing.

See Preferences?

Thanks for the picture, I had clicked all the midi preference things there except that, Having gone straight to the subfolder, I had seen export at 480, and wondered if that was the setting. Now I see it is at 120 per 16th note, which it would be for 1/4.