beck@tessa.iaf.uiowa.edu (Steven C. Beck) (05/21/91)
Thank you all for the replies. I guess I should have given a bit more
information in my original post "A call for digitizers". We are currently
using a 78/99 Eikonix digitizer. We are quit happy with the actual digitizing
mechanism ( the 2048 linear array photo diodes ) but the surrounding hardware
sucks. The columnar light source is completely useless to us because 1.) the
gradient caused by the sun bursting effect of the light source makes the
acquisition of information requiring a homogeneous field all but impossible.
In fact, we purchased a variable intensity grade 5 light box from Gordon
instruments for approx $1k and use it instead. 2.) the sun burst
wouldn't be so bad if we could align the light source such that the center of
the burst is at the center of the acquired image. We've had Eikonix in 3 times
(at approx $2k per visit) to see if they could align it. We figure we waisted
$6k. The head on the camera itself is as far from a precision instrument as I
care to imagine considering the money we paid for it in 1986 so even if we could
align the light source, we can't garuntee that the head will be in the same
place every time. Maybe the newer models are better but last I heard, Eidonix
didn't exist anymore except for the support crew.
We are also using 2 video cameras from Hamamatsu (1 newvicon and 1
plumicon tube), 1 microtek flat bed (300 dpi), a real time RGB video camera
from ColorTek (terrible resolution), and an FG100 video frame grabber from
somewhere (can't remember off the top of my head). Video cameras don't
give us enough resolution or clarity for density info. The Microtek scanner
is real impressive as long as you're using positives and as long as the
originals are sufficiently large that 300 dpi gives a good population of
digitized pixels. What happens if what we are after is sufficiently small
so that at 300 dpi we have insufficient resolution? The nice thing about the
Eikonix is that no matter how close you get to your sample, you get 2048 X 2048.
Microteck has a modification that will allow us to digitize (acquire
images) from transparencies ($1.6k) but they will not let us demo it first (as
I said). Optical density implies transmission of light through your sample
and so even though this is a very nice scanner, it hasn't been usefull to
us yet (except we make really cool icons for our silicon graphics workstations
with it...and we never, never digitize our butts...ever!!!...ahem)
Thanks again for all the response. Still looking for digitizers
(image acquisition devices).
--
Steven Craig Beck __ __| \ __| "Sometimes I'm so clever,
Image Analysis Facility | / \ | I don't even understand what
University of Iowa | _____ \ __| I've said."
Iowa City, Iowa ______| _/ _\ _|