Re: Fusing before or after

DaveN wrote:
> I don't know if this has been asked before (hard question to ask in a
> search) but why don't people fuse their images before making
> panoramas?  By that I mean the software for making panoramas (the
> hugin clone ptgui and autopano pro) seem to remap all the images to
> create differently exposed panoramas and then blend the panoramas.
> Wouldn't it be more efficient to exposure fuse the images and then
> make the panorama?

There are a number of pros and cons.

IF the bracketed shots were taken using a (good) tripod,
the images can be fused prior to stitching.

However, this makes subsequent use of exposure optimisation
in hugin "questionable", since the numerical basis of the optimisation
is destroyed by the (clever and generally desirable) things enfuse does.

The other possibility is that fusing is on a PER shot basis, and may
create edge conditions between successive shots in the panorama
that might cause difficulties for enblend.

However, post-fusing requires the shots to be aligned.
One way round this is to create a hugin project of the
"middle" exposure in the bracket set, and then use this
as a template for the more extreme exposures. This avoids
the difficulties of placing control points on the extreme
exposures at the ends of the bracketing. This only works
for tripod-taken sets.

Finally, pre fusing IS computationally efficient; if you repeatedly
"tweak" your panorama project, having all the fusing done as a pre-stage
is clearly efficient. Further, fusing a bracketed set of
stitched panoramas is a massively RAM intensive activity, whereas
fusing the shots separately might well fit in RAM.

    BugBear (pre fuser, on balance)

--~--~---------~--~----~------------~-------~--~----~
You received this message because you are subscribed to the Google Groups "hugin and other free panoramic software" group.
A list of frequently asked questions is available at: http://wiki.panotools.org/Hugin_FAQ
To post to this group, send email to hugin-ptx@...
To unsubscribe from this group, send email to hugin-ptx-unsubscribe@...
For more options, visit this group at http://groups.google.com/group/hugin-ptx
-~----------~----~----~----~------~----~------~--~---