Using Compare Mode

Compare mode splits the map into two side-by-side panes with a synced camera and region, so you can view SST against chlorophyll, or two different passes of the same layer, at once.

How do I turn on compare mode?

The toggle sits at the left end of the toolbar cluster on desktop and tablet. On narrow screens it moves into the map overlays menu as a "Compare mode" row instead, to keep the toolbar usable at that width. Compare mode is available on every plan, including as a guest. The only thing that turns it off is a viewport under 500px tall, where two panes can't fit usefully.

What syncs between the two panes, and what doesn't?

Camera position, the active region, and a pinned click readout all sync: pan or zoom either pane and the other follows, switch regions on one and the other switches too, and clicking one pane places the same readout at the matching coordinate in both. Layer (SST vs. chlorophyll) and data source stay independent per pane, so you can put SST on top and chlorophyll on the bottom and leave them there.

What does the bottom pane show the first time I turn it on?

The first time you ever turn compare mode on, the bottom pane clones the top pane's current region and is set to whichever layer the top pane isn't on, so opening compare from an SST view gives you chlorophyll below it, ready to compare immediately. That clone only happens once. Nothing stops you from switching the bottom pane's layer back afterward, and on a later visit with compare mode already on, both panes simply restore whatever you left them on last time, so two panes on the same layer is possible if you set it up that way.

Do the two timelines move together?

Not by default. Each pane steps through its own passes and composites independently unless you explicitly link them. See timeline lock for how linking works and what it does when the two panes don't have a matching pass to jump to.

Does compare mode change what I can see on my plan?

No, compare mode itself is free on every plan. Satellite passes, buoys, and alerts inside either pane still follow your plan's region access exactly as they do outside compare mode. See pricing for what each plan includes, or how to use Chlorofishy for the rest of the map.