? abt MH Bulb, PAR, and Ballast.

I recently ordered my Phoenix 14K bulbs to replace my yellow Odyssea bulbs.
They are in transit.
However, the Odyssea bulbs that im running on the 2011 Odyssea ballasts are putting out quite a but of light. Very bright but I don't have a PAR meter or anything like that.
I got two 250W Coral Keepers bulbs today and just put them on to test them out.
The color they put out is astonishing compared to the Odyssea bulbs.
However, I do have 1 concern. To my eyes, the coral keepers 250w bulb seems a bit less bright than the odyssea on the same ballast.
Is this intensity as a result of bulb to ballast combination?
Or does a MH ballast put out a steady amt of wattage for any type of bulb?
Are my eyes playing tricks on me?
I'm having trouble articulating this question properly so plz ask any questions for clarification if you need.
Any help at all is greatly appreciated.

 

bump!

 

Here's a pic.
Odyssea bulb in the centre and coral keepers bulbs on wither end.
All running on Odyssea 2011 ballasts