> The colour will quickly go from bright white to yellow as you dim,
> as an ordinary filament bulb would do with a dimmer. "Soft start"
> dimmers are recommended, the type depending on how the
> bulb voltage is derived, ie a wound or "electronic" transformer.
> I assume "soft start" implies zero-switching.

You can dim it without changing the color temperature, by using a shutter,
but you will have a LOT of heat to get rid of.