The Sony has a zoom range of 59" to 93" from 283cm away.https://www.projectorcentral.com/Sony-VPL-HW65ES-projection-calculator-pro.htm
Page 4 of the manual directs you to the location of the zoom lever on the projector, and details are on page 10 of the manual.https://www.projectorcentral.com/pdf/projector_manual_9050.pdf
If you are just confused because the calculator shows 77", that's because that's the CENTER of the zoom range.
Set the image diagonal to 90" on the calculator, then use the 'Zoom Range' slider to adjust how far away the projector may be for that specific size image.
FYI: WIth a 90" diagonal, the lens to screen distance may be between 270cm and 429cm.
Hope that clears things up a bit.
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