Channel Break-out then a retrace at 61.8% & closed above channel top.
Safe entry can be above the red line on the below chart with stop loss below 1780. Targets can be 1850-1869-1893-1923
In lower time frame Nifty approaching 1.618 retracement. RSI also overbought so expecting a small correction.
Incase of Preopen Above 10140 the entire setup will be invalid. Can initiate long at bottom