Good day everyone,
I have the Lutron Serena shades in a few windows in my house. Is there a solar sensor that can detect when the solar rays are going thru the window, so I can close the shades. What I mean is I want to close the shades partially or totally when the rays are going right thru the window, like in the early morning or late in the afternoon. I hope this make sense.
Thank you
You should be able to use any sensor that reports lux (well, any that reports lux with reasonable ranges) to achieve this. Unfortunately, you may have to do some experimentation to see exactly what works for you--e.g., what values you'd consider "sunny enough" to want to close the shades.
I've used the Dome Motion sensor (DMMS1) and think it reports pretty good values. I have a Zooz 4-in-1 and an Aeon Multi 6 but haven't looked as closely at the values they provide (the Aeon is pretty expensive and might be a bit big to fit in a window, too). For something a bit less noticeable, the Sensative Strips Comfort measure lux, but I've never used them so can't speak from experience, and I also find them quite pricey (and to boot, their size means a non-user-serviceable battery, which I don't generally like).
Others may have some other ideas. Personally, I just adjust my blinds based on mode, which is driven by time of day and sunrise/sunset times. Eventually, I'd like to work outdoor lux level into there somehow (in my case probably just one outdoor reading and not something in each window)--I'm just not there yet. 
Thanks for the info. I will look into those sensors. Lutron Serena should have those sensors built-in as part of the shades. Paying $1,000 per shade should give you that feature already included in my opinion.
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