Check the Price Axis Before Moving a Level

An SPX strike is not automatically an ES contract price. Nor should you add basis whenever you see ES_SPX: some feeds already use the futures price axis.

Compare the actual displays

Open HuntingFlow beside your desktop plugin. Record the web symbol, exact futures contract, timestamps and the name of the level.

1. Separate the options source instrument from the displayed price axis.
2. Check the contract: front month, deferred month and back-adjusted continuous charts can differ.
3. Check whether conversion is already applied. Do not add basis again to pre-adjusted ES_SPX / NQ_NDX data; inspect the plugin's mapping settings.
4. Compare the same instant and metric. Today's basis cannot simply repair yesterday's chart, and C1 is not every possible Gamma peak.
5. If mapping is unclear, retain both readings and report the contract, settings and timestamps rather than shifting levels until they look right.

Illustrative double conversion

Suppose cash is 6000 and futures are 6012. A simple contemporaneous additive mapping would move a cash reference at 6020 to 6032. If the feed already returns 6032, adding another 12 is incorrect. This example does not imply that every mapping uses a fixed additive basis.

Outside options trading hours

Futures may keep trading while exposure remains at its latest valid options session. An updating futures price does not establish that exposure is updating too. Check data time.

Exercise

Annotate paired web and plugin screenshots with symbol, contract, metric and conversion settings. Explain the discrepancy before watching subsequent price action; do not tune mappings to fit the outcome.

Related: Metric basis · Futures track.