Like most of you, I was really unhappy with my stock headlamps. After lots of reading on this site, I upgraded the harness (slee) and the lamps (hella E-code). Huge improvement. But...big but...while driving on dark windy mtn roads, the hella's had a problem. I could drive comfortably at 50-55 mph, but the cut-off was so sharp that any faster and I was driving outside my reaction times. Since many of my dark stormy drives are late nights in the mountains (when I'm tired) I have a particular concern about good lighting. The hella's were a huge improvement, but not good enough.
I noticed a few posts about Cibie's, and also some positive comments about Daniel Stern. So I gave him a call....here's his response:
Start Quote from Daniel Stern
Take a look at
http://dastern.torque.net/Photometry/Isocomparo.html
These are isocandela diagrams for Cibie and Hella 7" round headlamp units.
If you're not familiar with isocandela diagrams, these will look like
random squiggles and lines. Think of it as a topographic or "contour" map
of the correctly-aimed beam pattern. Each differently-colored line
represents the threshold of a particular intensity level, with the color
legend located to the right of the isocandela diagram. The diagram is
plotted on a chart calibrated in degrees. Straight ahead is represented by
(0,0), that is, zero degrees up-down and zero degrees left-right.
To get a mental approximation of the units and amounts under discussion
here:
Parking lamp: About 60 to 100 candela
Front turn signal: About 500 candela
Glaring high-beam daytime running lamps (e.g. Saturn): 8000 candela
The parameters to pay attention to are the luminous flux (total amount of
light within the beam), the maximum intensity and its location within the
beam relative to the axial point (H,V) -- the less downward/rightward
offset, the longer the seeing distance -- stray light outside the beam
pattern and effective beam width (contained within the dark-turquoise 500
candela contour)
Things to notice about these two diagrams:
(1) The Cibie produces a much wider beam pattern than the Hella. The 1000
candela line of the Cibie's beam pattern extends from 25 degrees Left to
25 degrees right, while the 1000 candela line of the Hella extends from 18
degrees Left to 20 degrees Right. At a distance of 50 feet from the car,
this means the 1000 candela-and-brighter portion of the Hella's beam is
10.5 feet narrower than that of the Cibie. The 300 cd contour of the
Cibie's pattern is *far* wider, extending from 43 degrees Left to 50
degrees Right, compared to 26 Left to 25 Right for the Hella. This means
the overall useful width of the beam pattern at 25 feet from the car, as
perceived by the driver, will be 40.7 feet for the Cibie and 22.3 feet for
the Hella.
2) The total luminous flux (overall amount of light) within the beam
pattern is 695 lumens for the Cibie, 463 lumens for the Hella - the Cibie
is 50.1% more efficient. (the TLF data is listed as "Luminous Flux" in the
readings up above the isocandela diagram)
The high beams for these two lamps (isocandela diagrams not yet scanned
in) are very similar in overall performance and amount of light -- the
critical difference is that the Cibie's high beam hot spot is located
closer to (0,0) and closer to its low beam hot spot. The Hella's high beam
and low beam hot spots are separated by a fairly large vertical amount,
such that setting the lows where they belong results in most of the high
beam light going up in the trees, but pulling the high beams down so they
send light straight ahead puts the low beams 10 feet in front of the car.
End Quote from Daniel Stern
I purchased the Cibie's. Installed them with 100/90 Narva bulbs. (I tried lots of different bulbs with the Hella's. Lots. ) Did 500 miles in the mountains with them this week, some of which was dark, rainy, late at night (and I was tired). Net result is a huge improvement over the hella's. (Anybody want to buy some hella E-code lamps?) Driving was far easier, less stressful, greater vis. Only neg was when the road rose in front of me (aka a hill) the cutt-off of the lens made for a blind section of the road (the section of the road that was "above" the cut-off). This is a small complaint. All in all, these are a fantastic lamp. The hella's were good, and had a nice high beam. The cibie's are awesome, and t he high-beams are astonishing.
Don't even think about buying Hella's. Only buy the Cibie's.
If you have the Hella's already, and drive challenging roads at night, buy the Cibie's right away. It's that big an improvement. I can't tell you how big a difference it was at 11:30 at night (after a 5:00am wake up) to have great visibility in a windy rough surface moutain road, with potential black ice...
Usually I'm kind of lazziez-faire about what people do, but in this case I'm going to be very directive:
Use an upgraded wiring harness (slee or similar).
Use Cibie e-code lamps.
Use 100/90 Narvabulbs.
Aim correctly (refer to tech section on Daniel Stern website)
Drive safely friends.
I noticed a few posts about Cibie's, and also some positive comments about Daniel Stern. So I gave him a call....here's his response:
Start Quote from Daniel Stern
Take a look at
http://dastern.torque.net/Photometry/Isocomparo.html
These are isocandela diagrams for Cibie and Hella 7" round headlamp units.
If you're not familiar with isocandela diagrams, these will look like
random squiggles and lines. Think of it as a topographic or "contour" map
of the correctly-aimed beam pattern. Each differently-colored line
represents the threshold of a particular intensity level, with the color
legend located to the right of the isocandela diagram. The diagram is
plotted on a chart calibrated in degrees. Straight ahead is represented by
(0,0), that is, zero degrees up-down and zero degrees left-right.
To get a mental approximation of the units and amounts under discussion
here:
Parking lamp: About 60 to 100 candela
Front turn signal: About 500 candela
Glaring high-beam daytime running lamps (e.g. Saturn): 8000 candela
The parameters to pay attention to are the luminous flux (total amount of
light within the beam), the maximum intensity and its location within the
beam relative to the axial point (H,V) -- the less downward/rightward
offset, the longer the seeing distance -- stray light outside the beam
pattern and effective beam width (contained within the dark-turquoise 500
candela contour)
Things to notice about these two diagrams:
(1) The Cibie produces a much wider beam pattern than the Hella. The 1000
candela line of the Cibie's beam pattern extends from 25 degrees Left to
25 degrees right, while the 1000 candela line of the Hella extends from 18
degrees Left to 20 degrees Right. At a distance of 50 feet from the car,
this means the 1000 candela-and-brighter portion of the Hella's beam is
10.5 feet narrower than that of the Cibie. The 300 cd contour of the
Cibie's pattern is *far* wider, extending from 43 degrees Left to 50
degrees Right, compared to 26 Left to 25 Right for the Hella. This means
the overall useful width of the beam pattern at 25 feet from the car, as
perceived by the driver, will be 40.7 feet for the Cibie and 22.3 feet for
the Hella.
2) The total luminous flux (overall amount of light) within the beam
pattern is 695 lumens for the Cibie, 463 lumens for the Hella - the Cibie
is 50.1% more efficient. (the TLF data is listed as "Luminous Flux" in the
readings up above the isocandela diagram)
The high beams for these two lamps (isocandela diagrams not yet scanned
in) are very similar in overall performance and amount of light -- the
critical difference is that the Cibie's high beam hot spot is located
closer to (0,0) and closer to its low beam hot spot. The Hella's high beam
and low beam hot spots are separated by a fairly large vertical amount,
such that setting the lows where they belong results in most of the high
beam light going up in the trees, but pulling the high beams down so they
send light straight ahead puts the low beams 10 feet in front of the car.
End Quote from Daniel Stern
I purchased the Cibie's. Installed them with 100/90 Narva bulbs. (I tried lots of different bulbs with the Hella's. Lots. ) Did 500 miles in the mountains with them this week, some of which was dark, rainy, late at night (and I was tired). Net result is a huge improvement over the hella's. (Anybody want to buy some hella E-code lamps?) Driving was far easier, less stressful, greater vis. Only neg was when the road rose in front of me (aka a hill) the cutt-off of the lens made for a blind section of the road (the section of the road that was "above" the cut-off). This is a small complaint. All in all, these are a fantastic lamp. The hella's were good, and had a nice high beam. The cibie's are awesome, and t he high-beams are astonishing.
Don't even think about buying Hella's. Only buy the Cibie's.
If you have the Hella's already, and drive challenging roads at night, buy the Cibie's right away. It's that big an improvement. I can't tell you how big a difference it was at 11:30 at night (after a 5:00am wake up) to have great visibility in a windy rough surface moutain road, with potential black ice...
Usually I'm kind of lazziez-faire about what people do, but in this case I'm going to be very directive:
Use an upgraded wiring harness (slee or similar).
Use Cibie e-code lamps.
Use 100/90 Narvabulbs.
Aim correctly (refer to tech section on Daniel Stern website)
Drive safely friends.
(these, with the yellow bulbs) were stock(as required by law) in french cruisers untill the early 80's I think. 
