Although white LEDs appear to be white (bluish white), the spectrum is made
up of blue line and yellow band components. The line is fairly broad for an
LED, but it's still a line. The resulting light may, depending on the exact
design, be lacking in the green and red areas of the spectrum. That may
cause problems, but it's still worth the experiment. Let us know what
happens.

"E Pericoloso Sporgersi" <PericolosoSporgersi.net> wrote in message
news:MPG.1988ad1923060b989682newsbin.telenet.be.. .
>
> Hi people,
>
> The traditional light source for dental photography is the ringlight. The
> constant light (Samigon Halo-Light FRL-1), the more sophisticated pulse
flash
> (Sunpak DX12R and DX-8R) and the fibre-optic based model (Olympus
Ringlight)
> offer pre-exposure lighting for better focusing. But the cost of a digital
SLR
> body, dedicated macro lens and ringlight is quite high, and these things
are
> bulky, heavy and power hungry. Of course the photographic quality is
superb,
> but it far exceeds my needs. In my case a cheaper and more humble system
makes
> much more sense.
>
> I recently bought a moderately priced, all-purpose digital camera, which
> features a superb zoom lens with adequate macro capability. Unfortunately,
its
> built-in flash is useless for close-up work and it lacks an external flash
> synchronisation.
>
> But do I actually have to use a pulse flash for dental photography? Is a
> constant light source not just as good, provided there is no heat and no
risk
> of bulb explosion?
>
> I am convinced that, for real close-up work, a ring of white light LEDs
would
> perform as well, but would, in weight, compactness and power consumption
> resoundingly beat the traditional ringlight. I can think of only one
possible
> disadvantage: the color spectrum might be off, but the white balance can
be
> automatically corrected by the camera's internal software.
>
> Searching on the net, I found several brands and designs of LED
ringlights, but
> only one specifically designed for photography. Unfortunately the Nikon
Coolpix
> Ringlight can not be made to fit my camera's lens. So I shall have to
build
> one myself.
>
> construction:
> [url]http://users.pandora.be/cisken/foto/ringlight_schematic_lores_50pc.jpg[/url]
>
> testpics:
> [url]http://users.pandora.be/cisken/foto/plastic_model_a.JPG[/url]
>
> [url]http://users.pandora.be/cisken/foto/plastic_model_b.JPG[/url]
>
> [url]http://users.pandora.be/cisken/foto/plastic_model_c.jpg[/url]
>
> [url]http://users.pandora.be/cisken/foto/dental_smurf.JPG[/url]
>
> [url]http://users.pandora.be/cisken/foto/live_patient.JPG[/url]
>
> What do you think about the feasibility of my project. I would also very
much
> appreciate your advice.
>
> Please send your reply in dutch, english, german or french.
>
> TIA,
> Francis
> Mol, Belgium
>
> --
> Francis Kennis, aka Pericoloso Sporgersi
> [email]transWIPEMEkenbusmail.net[/email]
>