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P3D Best viewers - Part II
I am now moving to the "electrical" or illumination components.
Brightness is a function of the light bulb, power source, reflector,
and geometry of the illumination housing. You can change bulbs, power
sources and reflectors to make illumination as bright and even as
possible. You mentioned:
>On most of my tests using an original GE bulb verses a newer halogen
>bulb, I sometimes feel that the standard bulb is brighter.
This is a sign of trouble. An original no. 14 GE bulb runs at 0.3A
while a halogen bulb runs at 0.8A. I can assure you that the halogen
bulb is significantly brighter, if powered at the rated voltage. Let
me explain what does "powered at the rated voltage" means. Both the
No. 14 and the halogen bulb are rated 2.5V. The actual voltage
applied on the bulb might vary. If you use exhausted batteries, or
batteries or transformers that cannot supply the needed current then
you will get a voltage drop and you will not not take advantage of the
extra halogen bust. For example, an transformer rated 2.5V/300mA will
make the no. 14 bulb light up well at 2.5 V while the halogen bulb
will be dim at 1.0V. I suggest that you use fresh batteries and
measure the actual voltage of the bulb with a voltmeter if in doubt.
You asked:
>Do you believe that the Red-button is still better in all respects to
>a Kodaslide II ?
What I think and what others think can be two different things and
we might all be correct. I prefer the red button viewer. Others
prefer the Kodaslide II viewer. The Kodaslide II viewer has large
clear lenses (larger than the RB), nice styling (perhaps it fits better
in the face of some people) and is used primarily in AC (even though it
can be switched to DC). Now, AC bulbs have a distinctly orange color,
as compared to the halogen 2.5V bulbs. I believe that many people
prefer this warm illumination which affects their choice of viewer.
As I've said before, I think it is better to view the slides as they
are (with as close to daylight color of illumination as possible).
If someone prefers warmer pictures in general, then they should use
warming filters in the camera in the first place.
I noticed you mentioned ,"finger-free lighting" in your list of viewer
desirable qualities. This feature is not in my list, as I believe it
causes more trouble that benefits. In a sequential or demonstration
viewer I understand how this is an advantage but in a single-slide
viewer it is easy to press a button while looking through the viewer.
The drawback of these designs (one example is the Life-Like viewer) is
that this "finger-free" operation is achieved with electrical contacts
that are not easily accessible for cleaning. Flicker is common at
points of contacts and these need to be cleaned from time to time.
More contacts which not easily accessible is a problem IMO.
The bottom line is that we can talk for hours and never agree on which
is the best viewer and why. Even for the most fundamental, optical
quality, we might not agree because some things that bother me (like
chromatic aberration) might not bother you as much. Mechanical
construction or "general feel"? Forget it! Totally subjective!
Illumination is a bit more objective because we can measure it, but it
is easy to change it in most viewers. And if we agree that, say, the
deWijs "Comby" is a great viewer, we still have to talk about availability
and prices. Better, yes, but at what cost? Or, "is it worth it???"
Here are two viewers that people have said they liked, not mentioned
above: TDC Deluxe, Wollensak.
Good luck in the pursuit of finding the "best viewer". When done,
please let me know what you find to be the best!
George Themelis
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