Having spent years as a professional portrait photographer, I came by many tricks of the trade involving readily available materials. One such trick is known as an "Oil Spot Photometer", which can help you equalize the brightness of two or more light sources.

For simple setup instructions, visit:

Oct 2, 2020 Oil Spot Photometer Oil Spot Photometer

When an oil spot on a card is illuminated equally from both sides, it mysteriously disappears. This allows you to compare the brightness of the light sources on either side of the card.

The implications for Home Automation, of course, is knowing the preset dim levels needed to balance a room's lighting, without guessing. Just bear in mind that dimmer levels and bulb output are rarely linear, so you may have to take photometer readings at various brightness levels to create a lookup table (for use in MSR, etc.).

I have been wondering what to post here so bear with me as I am just having a bit of fun given the fact that I haven't had much to fix, improve on or optimize for my home automation setup, I just added a scene today to make a TTS announcement to remind me to plug in my car when its level is low. Not really a necessity but since I have not been commuting anymore for a few months, I caught myself a few times wishing I had recharged my car the day before.

This is what it looks like on openLuup:

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I reused a SiteSensor device which was polling my HomeAssistant integration for its lock status (Yes I can get openLuup to lock and unlock my car remotely) and made Home Assistant send the battery status.

To do this, I added a rest service command on home assistant:

rest_command: bmw_bat: url: "http://openLuupIP:3480/data_request?id=variableset&DeviceNum=26&serviceId=urn:micasaverde-com:serviceId:HaDevice1&Variable=BatteryLevel&Value={{states('sensor.i3_charging_level_hv')}}"

Note the device number which will need to be the device you want to send the battery status to and the home assistant entity which you will have to replace with the one you want. Then I created an automation on home assistant to trigger this service whenever the entity state changes.
Screen Shot 2021-03-08 at 3.20.36 PM.png Screen Shot 2021-03-08 at 3.20.46 PM.png

After that I just simply created a scene on openLuup to watch the battery level variable and do whatever I need to do with it.

This is an example of syncing entities in home-assistant to openLuup. I have a number of other similar integrations...