PanoTools NG:
Re: Sigma 8 F3.5 and its sharpness
John Houghton 2007-May-16 06:45:11
--- In #removed#, Paul F <fawley@...> wrote:
>
> some images only have 10 or so control points in odd places, others
> have 30 or more...
> what am I missing?
>
Calibrate your lens. Control points serve two main purposes. The
first is to enable the optimizer to evaluate the lens parameters, and
you need a good spread of points for this. The second purpose is is
to align the images with each other, and you need only a few points
per seam for this. So if you have already calibrated your lens, you
only require a few intelligently placed points per seam. Place the
points only on distant (stationary) features for which parallax isn't
an issue. Resist the temptation to put points on nearby objects,
i.e. don't try to use the optimizer to correct parallax errors.
The optimizer should then give a good report, but there will almost
certainly be visible stitching errors due to parallax effects. These
need to be corrected in postprocessing (or sometimes by using the
morphing option). Some of the apparently perfect handheld stitches
are the product of many hours in spent in post. Care when taking the
photos will hopefully help to reduce this time to a minimum.
Anticipate where the seam lines are going to fall and aim to position
them in areas less sensitive to parallax errors.
John
--
<*> Wiki: http://wiki.panotools.org/
<*> Nabble (web) http://www.nabble.com/PanoToolsNG-f15658.html
<*> NG Member Map http://www.panomaps.com/ng/
Yahoo! Groups Links
<*> To visit your group on the web, go to:
http://groups.yahoo.com/group/PanoToolsNG/
<*> Your email settings:
Individual Email | Traditional
<*> To change settings online go to:
http://groups.yahoo.com/group/PanoToolsNG/join
(Yahoo! ID required)
<*> To change settings via email:
mailto:#removed#
mailto:#removed#
<*> To unsubscribe from this group, send an email to:
#removed#
<*> Your use of Yahoo! Groups is subject to:
http://docs.yahoo.com/info/terms/