Click the control or press Q to activate.
The Quantity control, part of the Main Diffraction Spikes control group, allows you to increase or decrease the number of highlights (ranked by brightness) that are given effects. You can put effects on just a very few of the brightest highlights or you can include more, dimmer ones.
Higher Quantity values put effects on more, dimmer highlights.
When you change the Quantity control all of the effect brightnesses are ranged, with the highlights whose brightnesses are just above the minimum brightness threshold being given effects that barely show.
Note that this control affects all of the effects - Primary Spikes, Secondary Spikes, Soft Flare, and Ring Flare.
When the Highlight Analysis configuration option is set to Automatic Analysis and the plug-in is started in the Basic Controls mode with the Quantity control set to 0, the analysis of the image is deferred until such time as the Quantity control is moved off of 0.
If the Highlight Analysis configuration option is set to Manual Analysis, the Quantity control operates in its normal manner and no analysis will be performed unless you click on the [ Analyze ] button.
Since Highlight Analysis can be time consuming, deferring analysis in this fashion facilitates quick usage of the plug-in in a purely manual mode, in which you use the Edit Tool to double-click to add your own effects.