-------- Original Message --------
Subject: Re: Re: Next Engine scanner protocol
Date: Mon, 9 Apr 2012 16:22:25 -0400
From: Caley Orr <caley....@gmail.com>
To: morphmet@morphometrics.org
I concur with Heather that the HD Pro software is absolutely essential
and also that doing the final alignment in Geomagic or another software
program usually works better. Be sure to download the updates to the HD
software as they are released, because NextEngine has made a lot of
improvements over the last few years. However, with your small samples,
you'll probably want to use one of the standard or high definition
settings (so slower speed) depending on how small your specimens are,
but not necessarily the maximum. Try the highest SD or first or second
notch in the HD zone. You can offset the long scan time by doing fewer
divisions. Nine divisions seems to work out pretty well in most cases
and 16 on the HD setting will probably oversample the surface and make
the files too large to work with. The HD settings have gotten much
better and there seems to be less noise than there used to be. Use the
Macro setting and pay attention to the suggested distance from the
scanner (ends up being ~16cm, I believe).
I would try the Align function for putting together the divisions using
the colored 'pins' to match homologous points, use the Volume Merge as
Heather suggests, and then output the merged divisions as a PLY file.
If you are attempting to get the whole skull scanned, then reorient the
specimen, repeat the scan steps and output that second merged scan as a
separate PLY file. Then do the merge the two PLYs in Geomagic or similar.
I don't bother with the tilt or anything (doing mostly hand bones), so
have no advice there.
Unless these skulls are really tiny (and depending on what anatomy you
need to see), the NextEngine can do a decent job, but can take some
fiddling. Good luck!
-Caley
--
Caley M. Orr, PhD
Research Instructor
Department of Anatomical Sciences
Health Sciences Center T-8 040
Stony Brook University
Stony Brook, NY 11794-8081
http://www.wix.com/caleyorr/phd
On Mon, Apr 9, 2012 at 3:41 PM, morphmet
<morphmet_modera...@morphometrics.org
<mailto:morphmet_modera...@morphometrics.org>> wrote:
-------- Original Message --------
Subject: Re: Next Engine scanner protocol
Date: Mon, 9 Apr 2012 14:09:32 -0400
From: Heather Garvin <heama...@aol.com <mailto:heama...@aol.com>>
To: morphmet@morphometrics.org <mailto:morphmet@morphometrics.org>
I haven't scanned anything that small(I was scanning human
skulls),but I
can tell you that paying the extra money for the HD Pro software
makes a
world of a difference. Not only does it give you higher quality scans,
but it cuts your scanning time pretty much in half.
Besides that, I was given advice by Matt Tocheri to use the maximum
number of divisions under the highest speed. This may sound
counter-intuitive, but the rationale is that you get better accuracy
when you have more regions of overlap (from different angles). With a
high degree of overlap you can obtain just as many surface points than
going more slowly over less divisions. Also in the slower speeds
(higher
dpi), it was suggested to me because the laser is going over each
region
more slowly, there's more of a chance it will pick up noise or reflect
back oddly, creating more inaccuracies. So I followed this advice with
human skulls (using the HD program, highest number of divisions,
fastest
speed). I'm not sure how it would work out on the smaller skulls.
Finally, the NextEngine software does okay aligning the divisions
from a
single scan (given that the object doesn't move). I use the "Volume
Merge" instead of any of the "fusion" options, to get a uniform mesh.
But I found that it really sucked at aligning more than one 360 degree
scan together (for example, if you took one 360 scan, changed position
and took another). So after each scan I would save the .ply and open it
in another program, such as GeoMagic or Rapidworks, and do the rest of
the aligning and merging in there. The problem is, these programs are
expensive, but if you have an associated engineering program they may
already have an institutional copy.
Hope this helps a little. Goodluck!
--Heather
*
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~__~~~~~~~~
Heather Garvin*
PhD Candidate
Center for Functional Anatomy & Evolution
Johns Hopkins School of Medicine
http://www.hopkinsmedicine.__org/fae/HMG.htm
<http://www.hopkinsmedicine.org/fae/HMG.htm>
hmgar...@gmail.com <mailto:hmgar...@gmail.com>
-----Original Message-----
From: morphmet <morphmet_moderator@__morphometrics.org
<mailto:morphmet_modera...@morphometrics.org>>
To: morphmet <morphmet@morphometrics.org
<mailto:morphmet@morphometrics.org>>
Sent: Mon, Apr 9, 2012 1:56 pm
Subject: Next Engine scanner protocol
-------- Original Message --------
Subject: Next Engine scanner protocol
Date: Mon, 9 Apr 2012 18:01:31 +0200
From: Javier Santos<javiersantos3@hotmail.__com
<mailto:javiersant...@hotmail.com>
<mailto:javiersantos3@hotmail.__com
<mailto:javiersant...@hotmail.com>>>
To: Morphomet New Mailing
List<morphmet_moderator@__morphometrics.org
<mailto:morphmet_modera...@morphometrics.org>
<mailto:morphmet_moderator@__morphometrics.org
<mailto:morphmet_modera...@morphometrics.org>>>
Hello morphometricians,
I am working with snow vole skulls and have been provided a Next Engine
surface scanner to obtain my shape data. I have done various tests with
the scanner, but I still don't achieve the resolution I was
expecting in
the quality of the scans after alignment. I was hoping that
somebody who
has used or is using this scanner could give me some tips on how they
program the scanner to obtain their images, such as number of
divisions,
starting angle, starting tilt, etc. As well, any tip on what to use to
position and maintain the skull still during scanning (especially as I
use the optional robotic arm for the Next Engine scanner). I would also
appreciate any other useful information you might know on how to obtain
fine morphological data from micromammal skulls using other techniques,
software, etc. Thank you a lot in advance!
All the best,
Javier Santos
Museo Nacional de Ciencias Naturales (MNCN-CSIC)
Biodiversity and Evolutionary Biology Department
