if your not wearing a #12 welding screen than it ain't bright enough! "Hand-Sun H.I.D." 55w & 75w(for sale), Rocky 3w LED, Stanley 109 35w mod'd, Maxa-Beam Gen II, 55w hid/100w incan Vector Twin, 400w MH long arc, 100w MH mid arc. Amondotech n30.
What's the difference? Beamshots??
And I heard the voice of the Lord saying, "Whom shall I send, and who will go for us?" Then I said, "Here am I! Send me."
A tubular arc chamber will diffract the image of the arc to varying degrees depending on the viewing angle. Since the reflector takes a range of viewing angles, the thing it is trying to image will see varying degrees of refraction at different angles, leading to a less well focused beam. Think kind of how if you look at an object through a piece of glass at a sharp angle, the object appears to have changed in its location in space.
A round chamber minimizes this effect, since at any angle within the lamp's viewing angle the light is hitting the surface of the round chamber at a normal of ~90 degrees. Kind of like how if you look straight through a piece of glass at an object on the other side, the object will appear to be where it actually is.