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Light Report to Date (long and nerdy)

Here's my up to date homework for those wanting to explore options to better
lighting further than aero drop and swaps.  I blame/thank the list for making
me take this project to heart, hope you find it as en-"light"ening as I....

Key:  * '  Aeros = Common reference to dual European aero conversions
         * " quads = Common reference to 4 headlite systems 7, 4X6, 3X5, 5
         *  Euros = Common reference to upangle beam pattern on lows
         * zbeam = Common reference to fog type pattern on lows
         ' = European upangle pattern available only - beam looks like __/
 -0000- __/
        " =  Euro, zbeam, and Hella "Vision Plus" availble beam looks like
___-0000- ___

For measurements:

*  Hella lists 550' for max euro low beam pattern (beyond which is not
*  Hella lists 1000'-1200' for euro max distance hi beam pattern (100w


*  Euros are considered Parabolic lights (P)- The bigger the size of the
light the more the light.  Light pattern distribution by cover lense.
 Disadvantage:  Stray Light (hello)

*  DE Projection type light (DE)  Uses reflector, filter and lense to produce
more power and control with a smaller physical aperature.  Advantage:  No
Stray Light

*  FreeForm (FF) - Uses 50,000 reflector points to direct light precisely, no
lense distribution of light.  Newer lights use this technology.  Advantage:
 No Stray Light

*HID/DE, High Intensity Discharge, Xenon, Sodium Mercury gas (HID) - Offers
UP TO (reread this) 3 times the lumen output for the same watts as halogen
bulb in car applications. Creates a "blue" white light more like daylight.
 Advantage:  Lower amperage draw, No stray light

*  HID/FF High Intensity Discharge, Xenon, Sodium and Mercury gas (HID)- 2.5
times output of equal halogen.  Combines FF technology with lower wattage
bulbs.  Creates a "blue" white light more like daylight.  Advantage:  No
stray light, no lense correction necessary, lower amperage draw

Objective Technical Conclusions:  It seems the days of P lighting are over
now that CAD/CAM technology is the standard.  Short of getting the ultimate
and expensive HID lights, the next best would be a FF light, then a DE light,
then the euro P lighting.  Free Form technology is already at production car
levels, the new taurus comes to mind (sorry, all I could think of).  H3 bulbs
can be used in FF designed lights with E/W orientation, since light control
is at the reflector as well as lense.

Subjective Conclusions:

I found the conclusions above a surprise, I personally put DE lighting behind
P.  That now is modified.  It appears that P lighting in the H1/H2
driving/pencil (Rallye 4000, 2000, 3000 etc) is still accepted as the
standard next to the exclusive HID, tho FF is better than DE/P in fog
conditions.  The beam pattern of fogs in FF is really phenomenal, these
deserve a serious look.  For audis and/or space considerations, the DE beat
the P hands down.  Given the difference between quads and aero conversions on
lows(PvsP):  An aero conversion will have better light control vs rect quad
(size only - zbeams and Vision Plus lense pattern overtaking that argument).
 Aeros will have less light control to round quads as you add lumens, (round
light is more "controlled" in P lighting than a rectangular one, more stray
in the latter).  Any gains the aeros have really are at the expense of a non
equadistant lense to filiment, prolly a wash in performance, for the price
the quads will win hands down.  Seriously consider leaving the aero outside
bulbs stock, all references to P lighting list stray light as the compromise,
Lumens exponentially offering more stray.  100w in the inner highs are OK for
aeros, but again, the stray light for a rectangular P would be outperformed
by a 100w in a 5 3/4 round (less stray light).   H4 high wattage bulb gains
will be offset too much by stray light, especially given the complexity of a
shared low/high lense.    Certainly quads and aeros are prolly equal in the
H4 low, but given the H3 (E/W filiment) in the common aeros highs, the quad
inner high will outperform the aero in light control.   I am also more
comfortable with the old H3 is a no/no rule being discounted, now that FF
technology makes that null (reflector can now be designed to correct E/W
filament bulb spot design).  Be advised however, most current aeros with H3
are compromising beam control, regardless of lense.  Also compromising, all
NON FF H3 lights offered are too - the XL falls here to, tho has less stray
light (over H4 aero/quads lows) due to single duty lense.  

Where does this leave me?  Looks to be the FF technology is good enough to
give that a "shot in the fog" even with the H3 bulbs.  The quad conversion
will continue, as will my efforts to find out if FF technology will be in
quads anytime soon.  If it is, I will probably not convert the Urq to quad
rounds as was my intention for better P control.  I will however continue my
quest for quad rounds (regardless of FF/P) in the 5ktq, my old (and now
recently date stamped) proposed arguments on P lighting vs aeros is still

I have lots of documentation and data to help if the above needs
clarification.  More is on the way (aaack).  Hopefully, this will extinguish
some of the "flames" I've seen here.  Sorry for the length, please feel free
to post me for anything more detailed.  Lots of information will follow as I
move this technical data to the audis.  I have been posting proposed comparo
methodology and instrumentation to Phil and Eric.  Not convinced this
research furthers the need, but I will still entertain the exercise, if
someone else feels compelled.

End of Report

Scott Justusson, (SOL, emeritus)