What is the purpose of the "Einstein Dome Cover"?

My dome cover for my Einstein fell off during a shoot and broke, and I have been slow to replace it. What does it do, and should I replace it?


It can be seen here if the name does not register a photo for your mind. Its about the 8th one down, and called Einstein Dome Cover
http://www.paulcbuff.c​om/modelinglamps.php

lowers the temp apx 300-600??

My recollection is that PCB said the cover was to make the modeling light and the strobe light the same as a source. Thus the modeling light produces the same light pattern (quality) in a modifier that the strobe tube will produce.

That said, I doubt that there is usability concern other than the color temp shift.

From the Einsteinpage:

"A frosted pyrex dome protects the lamp and tube from damage and serves to reduce UV emission from the flashtube. It equalizes the effective size and shape of the modeling lamp and flashtube as the modeling lamp filament is in exactly the same focal point as the UV-coated flashtube, resulting in an extremely close relationship between the flash and modeling light. The dome lowers the color temperature by approx. 300K."