That has been my experience with the Silverstar bulbs as well. The theory
is that the human eye is more sensitive to bluer light (higher color
temperature), but I can't see the difference. My _guess_ is that light
response is logarithmic, and 15% is just too small to notice without very
sensitive tests. I know that is true for hearing: the smallest step you can
hear in volume is 3 db, which is about twice the power.
However, there are some bulbs that will work better. I've been using 2357
for several years now, which are a direct substitute for 1157. The tail
filaments are the same as 1157 (same brightness, same power); but the
brake/turn filament is optimized for more light output (at the expense of
lifetime). They do draw just slightly more power (2.20 amps instead of
2.10), but the light definitely seems brighter to me (rated 25% more
candlepower/lumens). The downside is that the brake/turn filament is only
rated for 400 hours of life, rather than the 1200 hours for the 1157. So
far that hasn't been a problem for me; but I'm in the habit of taking my
foot off the brake after the car behind me has stopped. There is also a
"long life" version from Sylvania, but I don't know the specifications on
it.
There was also a recent post on this list about 3496 bulbs (originally
written by Jim Sloane I believe), which I intend to try. They are supposed
to be even brighter than the 2357 (43cp vs 40), draw slightly less power (27
watts vs 28.2), and have a longer lifetime (600 hours vs 400). The downside
appears to be that they are more expensive, harder to find, and you may have
to buy a pack of 10 of them.
-- Randall
|