PTGui template
collection
Joost Nieuwenhuijse has written PTGui,
a wonderful front-end program to Helmut Dersch's Panorama
Tools that makes panorama stitching easier than it was when
I wrote my tutorial.
You will find a good step-by-step guide (read
it before this page !) on the use of PTgui by John Houghton
at http://homepage.ntlworld.com/j.houghton/pttute.htm.
Lutz Kretzschmar also gives insights and tips at http://www.stmuc.com/digicam/.
This page is not intended to be yet another
tutorial on the use of PTgui, but a collection of working samples
to try the program, and templates to apply to your own images.
What
do I need ?
What
do I get here ?
For each lens setting, you will find:
a description of the shooting technique,
how to crop the images if necessary and parameters optimization
strategies.
a PTgui template file to apply to
your own images shot using similar settings.
a zip file containing a set of ready
to stitch images (cropped and rotated when necessary) with
PTgui project file with control points, before and after
optimization.
an assembled panorama
for the sake of completeness, a Zip
file containing the original photographs, directly coming
from my Coolpix.
Is
it usable with my camera ?
Though I used
a Nikon Coolpix 990 for the samples, it is directly applicable
to the 950 which behaves similarly. I tried to provide a wide
range of focal length so that it can be easily used with other
cameras.
How the samples were photographed
?
In order to minimize download times, everything was
shot in VGA basic mode... so don't expect high quality ! Many more details and tips here.
How
do I test the samples ?
How
do I apply templates to my images ?
Launch PTgui
Import your images (in Source images
tab, press Add button then select all your images). Caution: you
must name images in alphanumeric order as your camera is
rotated clockwise.
Select template file (name.pts)
that best matches shooting method you used. To be able to
apply the template, number of images and lens type (rectilinear
[normal] or fisheye [full frame or circular]) must be the
same.
Place your control points (in Control
points tab). Three control points per image pair should
be enough.
Before running the optimizer, it's
a good idea to save your script!
Run the optimizer and watch carefully
the value displayed during the optimization process: it
should decrease to a value in the range 0.5 - 3 pixels (
if it doesn't, see here).
If the process is slow (many images), and the value displayed
doesn't decrease significantly anymore, you can press the
cancel button to freeze the optimized values at their current
state.
Apply the optimized values.
You can then verify that everything
went OK during the optimizing by checking the optimized
horizontal field of view (lens setting tab). Its value should
be close to your lens hfov - if not, go
here.
Hfov evaluation: Warren Young's
F'calc
can be handy, or you can use Ken Turkowski javascript
angle
of view calculator. Note though that none of them apply
to fisheye lenses
Now, stitch your panorama (in Create
Panorama tab, press Create Panorama). With the template
file as I provide it, PTgui will generate a JPEG file with
rather low resolution. You can view it as an image, or as
a VR scene (simply drag and drop the panorama image on
PTviewer
for windows or on its shortcut).
Why is my panorama low resolution
?
Since the samples used are low resolution, the templates
themselves are targeted to low-res panoramas (this minimizes
download time, and ensures that stitching will be reasonably
fast iven with a low power/low memory computer). To get a panorama
dimension matching resolution of your images, go to the Panorama
Settings tab, increase height value up to vertical size of your
images, and enlarge horizontal size proportionnaly. Caution: this can lead to
unreasonably large images, especially for wide angle images.
I'd
like to fine tune the seams between images
Then
layered Photoshop files will be the best choice. Select that
format in Panorama Settings tab. Some seams editing techniques
are described in my previous
tutorial. When using this format, take care though of generated
file size and stitching time.
No editing was done on the generated panoramas.
At least some cropping of the top/bottom of cylindrical panoramas
would have been useful, but I left them as-is for documentary
purposes
'Field of View
limited to 160 degrees'... Can I work around this limitation?
(adapted from PTfaq)
In the
2.5b1 and newer versions of Panorama Tools, the field of view
for fisheye images is limited to 160 degrees. If you are convinced
that you don't violate any patents by processing fisheye images,
read on:
Several users have removed the limitation by recompiling
Panorama Tools. Here: http://www.ueckermann.de/pano12
you will find updated pano12 files without the limitation.
Further, the 2.5a version of Panorama Tools did not have
this limitation. You can still download Panorama Tools 2.5a
from this site: http://home.no.net/dmaurer/~dersch/Index.htm.
As an alternative, you could remove the 160 degree limit by
modifying and recompiling the source code which is included
with Panorama Tools 2.5b2.
The
collection (click on thumbnails to
access)