29 Mar
2018
29 Mar
'18
4:25 a.m.
On 29/03/2018 05:26, Shaun Halstead via cctalk wrote:
Using the wrong filament orientation can cause some
weird artifacts
to appear on scanned images, because of the high magnification. I
strongly suspect that an attempt using an LED source would face
similar (and possibly worse) issues.
Light source. Due to lensing requirements, LED's
are probably out,
unless a way can be found to suitably diffuse or blend the source
without losing significant light. This requires a very strong light
source.
Yet there are plenty of LED light sources used in photomicroscopy so I
don't believe it's that hard to do,which is why I suggested it. I've
seen it done with a high-brightness 5mm LED, but if a bit more "oomph"
or a larger emitting area is required, there are inexpensive 1W and 3W
LEDs that look like they'd work. I'm no expert, but the biggest problem
in photomicroscopy seems to be the spectrum, which isn't really an issue
for monochrome microfiche.
--
Pete
Pete Turnbull