I own a coated phillips HPS lamp that came in my M-400 R2 a LOOONG time ago. What Darren has is a lot more rare than what I have, but still both are rare.
Coated HPS lamos were made because they were designed to go in old MV fixtures that were designed for coated lamps, The HPS coating Is not a phosphor, it's just a coating powder to scatter the light like coated MV lamps do.
I wish FCO's used more coated lamps cause the lighting distribution is MUCH better with a coated lamp than a clear lamp.
Coated HPS lamos were made because they were designed to go in old MV fixtures that were designed for coated lamps, The HPS coating Is not a phosphor, it's just a coating powder to scatter the light like coated MV lamps do.
I wish FCO's used more coated lamps cause the lighting distribution is MUCH better with a coated lamp than a clear lamp.
I believe the lower watt ED17 ones were more common since they used to come with residential HPS lights.