When I run a dimming routine with the SmartThings app connected via a Lutron Hub and Caseta dimmer the room LED (Toggled) lights do not smoothly dim or increase. It seems like more of a “step” sequence not a smooth transition over the given time interval. I don’t believe this is a Lutron Caseta hardware or LED (dimmable) issue since I can get a smooth transition controlling the lights from the Caseta wall control itself.
My ultimate goal is to have the room lights increase (smoothly) in brightness from 1% (minimum on level) to a maximum 100% brightness over 90 minutes and then immediately reverse and decrease (dim) from the 100% on state back down to 1% on over 90 minutes. Note: within the ST app the maximum duration appears to be 60 minutes.
That SmartThings routine action “dim/brighten gradually” is indeed a cloud based action that updates the state of the lights every 60 seconds or so. While it would work for every light even if they don’t have native transitions, it’s never going to be as smooth as invoking the native transition if available.
Now, for some lights using Zigbee there are custom drivers and, also for Matter, workarounds with the rules editor to call the native transitions. The problem is Lutron integration is not even local, is cloud based, so it probably doesn’t even support transitions, you can try the workaround checking if the setLevel attribute “rate” does something. I believe it won’t. In that case you could ask Lutron support to implement it or just ask how to use transitions from SmartThings.
Wall remotes use other proprietary protocols to communicate with the lights and achieve the desired effect and Home Assistant is also able to trigger native Lutron transitions but their integration is local and not cloud based so the feature set may be different.