1) Option Chain data: Option chain reveal the picture not revealed by Nifty . On PUT side, the highest total OI (5.99 lakhs) and higest fresh Put writing (2.90 lakhs) is at the strike of 27500. At ATM strike of 28100, OI build up (63,100) and Put writing ( 55,740) is 7th highest, which means that Put writers are not at all confident about 28100 acting as support. So where Put writers are confident? At strike of 27800 we have 2nd highest total OI (3.22 lakhs) and 3rd highest fresh Put writing (1.99 lakhs). And at strike of 27700, we have 3nd highest total OI and 2nd highest fresh Put writing. So for me 27700-27800 represents good support. On CALL side, total highest OI (4.64 lakhs) and highest fresh Call writing (1.81 lakhs) is seen at strike 28500. At ATM strike of 28100, total OI is 1.56 lakhs (low, but higher than that at PUT) and fresh Call writing is 41,720 (quite low). At 28000 strike total OI is 4.01 lakhs (2nd highest) but there is call unwinding (-32,480). At strike of 28400, we have 3rd highest total OI (2.44 lakhs) and 2nd highest fresh Call writing (1.46 lakhs), if we consider strikes between 28000 to 28500. Actually, 28400 also seems quite a lofty resistance,given OI build-up on Put side. So in a nut shell, even though there is no clear cut , support looks between 27700-27800.
2) On Charts- BNF made a strong green candle with higher high (just a bit more) and lower low just like Nifty , as compared to previous candle. While rising, BNF did create some Buying areas on chart. A reliable buying area is marked on 15 min chart. However, it the price comes into this region quite late in the session (i.e. after say 2.30 pm), then the prospect of BNF rising for intraday gains becomes dicey. So trade keeping this in mind. For shorts, 28278 is resistance where BNF can be shorted with good RR ratio.
All the best. Happy trading.