Tuesday, July 29, 2008

Too Much Headlight


From Science Daily; 2001

Study Shows High-Intensity-Discharge Headlights Improve Night Visibility

ScienceDaily (July 2, 2001) — TROY, N.Y. - Researchers at the Lighting Research Center (LRC) at Rensselaer Polytechnic Institute report that HID (high-intensity-discharge) headlights enable drivers to see more effectively at night than conventional tungsten-halogen lights.

The LRC study has recently been featured in USA Today and on the NBC Nightly News.

Based on field experiments in which drivers responded to objects in their field of vision while using both sorts of lighting, LRC researchers concluded that drivers using HIDs were better at "detecting edge-of-roadway hazards, such as pedestrians and animals."

From the British Journal of Medicine; 2003:
British Journal of Ophthalmology 2003;87:113-117
© 2003 BMJ Publishing Group

Why HID headlights bother older drivers
M A Mainster
, G T Timberlake

Department of Ophthalmology, University of Kansas Medical Center, 3901 Rainbow Boulevard, Kansas City, KS 66160-7379, USA

Correspondence to:
Martin A Mainster, PhD, MD, Department of Ophthalmology, University of Kansas Medical Center, 3901 Rainbow Boulevard, Kansas City, KS 66160-7379, USA;

Driving requires effective coordination of visual, motor, and cognitive skills. Visual skills are pushed to their limit at night by decreased illumination and by disabling glare from oncoming headlights. High intensity discharge (HID) headlamps project light farther down roads, improving their owner’s driving safety by increasing the time available for reaction to potential problems. Glare is proportional to headlamp brightness, however, so increasing headlamp brightness also increases potential glare for oncoming drivers, particularly on curving two lane roads. This problem is worse for older drivers because of their increased intraocular light scattering, glare sensitivity, and photostress recovery time. An analysis of automobile headlights, intraocular stray light, glare, and night driving shows that brightness rather than blueness is the primary reason for the visual problems that HID headlights can cause for older drivers who confront them. The increased light projected by HID headlights is potentially valuable, but serious questions remain regarding how and where it should be projected.

Not much has changed since these studies were made. Many luxury cars including high-riding SUVs use these headlight systems. The question is whether or not they really help the driver of the vehicle with the HID system as much as they distract other drivers who are being tailgated by them or drastically reduce the vision of on-coming drivers. I suspect that most drivers really don't believe HIDs are appropriately placed or directed in SUVs and trucks.

My own feeling is that there should be a sensing system on the back of all vehicles that turn on the backup lights whenever too much light is directed at the sensors... whether from high beams or HIDs that are too close. That would be an effective signal to either back off or pass.
If you insist of trying to distract others with your misaimed, misaligned, misplaced, HID headlights, you should be informed that your efforts are working... with an appropriate message.
As far as on-coming vehicles are concerned, old-fashioned high beams are a good signal, too. I use them on my F-250, as appropriate.


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Tracking Interest Rates


SEARCH BLOG: FEDERAL RESERVE for full versions... or use the Blog Archive pulldown menu.

February 3, 2006
Go back to 1999-2000 and see what the Fed did. They are following the same pattern for 2005-06. If it ain't broke, the Fed will fix it... and good!
August 29, 2006 The Federal Reserve always acts on old information... and is the only cause of U.S. recessions.
December 5, 2006 Last spring I wrote about what I saw to be a sharp downturn in the economy in the "rustbelt" states, particularly Michigan.
March 28, 2007
The Federal Reserve sees no need to cut interest rates in the light of adverse recent economic data, Ben Bernanke said on Wednesday.
The Fed chairman said ”to date, the incoming data have supported the view that the current stance of policy is likely to foster sustainable economic growth and a gradual ebbing in core inflation”.

July 21, 2007 My guess is that if there is an interest rate change, a cut is more likely than an increase. The key variables to be watching at this point are real estate prices and the inventory of unsold homes.
August 11, 2007 I suspect that within 6 months the Federal Reserve will be forced to lower interest rates before housing becomes a black hole.
September 11, 2007 It only means that the overall process has flaws guaranteeing it will be slow in responding to changes in the economy... and tend to over-react as a result.
September 18, 2007 I think a 4% rate is really what is needed to turn the economy back on the right course. The rate may not get there, but more cuts will be needed with employment rates down and foreclosure rates up.
October 25, 2007 How long will it be before I will be able to write: "The Federal Reserve lowered its lending rate to 4% in response to the collapse of the U.S. housing market and massive numbers of foreclosures that threaten the banking and mortgage sectors."
"Should the elevated turbulence persist, it would increase the possibility of further tightening in financial conditions for households and businesses," he said.

"Uncertainties about the economic outlook are unusually high right now," he said. "These uncertainties require flexible and pragmatic policymaking -- nimble is the adjective I used a few weeks ago."

December 11, 2007 Somehow the Fed misses the obvious.
[Image from:]
December 13, 2007 [from The Christian Science Monitor]
"The odds of a recession are now above 50 percent," says Mark Zandi, chief economist at Moody's "We are right on the edge of a recession in part because of the Fed's reluctance to reduce interest rates more aggressively." [see my comments of September 11]
January 7, 2008 The real problem now is that consumers can't rescue the economy and manufacturing, which is already weakening, will continue to weaken. We've gutted the forces that could avoid a downturn. The question is not whether there will be a recession, but can it be dampened sufficiently so that it is very short.
January 11, 2008 This is death by a thousand cuts.
January 13, 2008 [N.Y. Times]
“The question is not whether we will have a recession, but how deep and prolonged it will be,” said David Rosenberg, the chief North American economist at Merrill Lynch. “Even if the Fed’s moves are going to work, it will not show up until the later part of 2008 or 2009.
January 17, 2008 A few days ago, Anna Schwartz, nonagenarian economist, implicated the Federal Reserve as the cause of the present lending crisis [from the Telegraph - UK]:
The high priestess of US monetarism - a revered figure at the Fed - says the central bank is itself the chief cause of the credit bubble, and now seems stunned as the consequences of its own actions engulf the financial system. "The new group at the Fed is not equal to the problem that faces it," she says, daring to utter a thought that fellow critics mostly utter sotto voce.
January 22, 2008 The cut has become infected and a limb is in danger. Ben Bernanke is panicking and the Fed has its emergency triage team cutting rates... this time by 3/4%. ...

What should the Federal Reserve do now? Step back... and don't be so anxious to raise rates at the first sign of economic improvement.
Individuals and businesses need stability in their financial cost structures so that they can plan effectively and keep their ships afloat. Wildly fluctuating rates... regardless of what the absolute levels are... create problems. Either too much spending or too much fear. It's just not that difficult to comprehend. Why has it been so difficult for the Fed?

About Me

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Michigan, United States
Air Force (SAC) captain 1968-72. Retired after 35 years of business and logistical planning, including running a small business. Two sons with advanced degrees; one with a business and pre-law degree. Beautiful wife who has put up with me for 4 decades. Education: B.A. (Sociology major; minors in philosopy, English literature, and German) M.S. Operations Management (like a mixture of an MBA with logistical planning)