I would like to know how difficult is it for the lab to measure the CT and ET of a specified plus powered lens given all frame size and pd measurements.
I recently asked a lab to give me the (smallest) CT and ET of a +5.50DS RX cr39 1.5 single vision plastic lens for a specific frame for comparison purpose with a stock lens. they seem not able to do it , or were reluctant to do it (maybe it's because the calculations are too complex).
i was wondering how easy / difficult is it to do these calculations.
Would love to hear from the experts.
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