inside day

Applying a concept from a previous post, here's an intra-day example of using the largest range that corrected greater than 100%.
The example being the SPY from Wed. Oct. 6th.  There was an impulse momentum move 25-minutes into the open, that was erased (retraced > 100%) within 45-min.

Once this range was established, it is projected off of the next swing high/low, like so:

Once price displays some stability (look for a momentum bar) we can project this range off of the lows and see if we get a breakout:

Price corrects, and we look to see what will progress within the box:

In this case, price holds AGAIN within it's boundary:

We now get another ranger wherein price corrected 100% of it's momentum move:

We could either project this range off of the swing high, but that would just put the box at the previous lows, an obvious support level.  So, we can instead project the box off of the swing high (lower high) that followed, in which case it gives us an ultimate line in the sand:

 Price finds support, and we use this box projected off of the lows:

Towards the end of the day, price breaks out from this box and bounces between the Open price and the upper boundary of this box.  Considering today was an inside day following a trend day, these last 20-minutes provided a solid range for scalping: