> I found that you can use raw files, but it doesn't apply the modified
> exposure parameters from the xmp sidecar file.
How should it? It isn't and doesn't use ACR. Do you know of any RAW
converter that uses the sidecar files of the another one?
> Is this how it is supposed to work? I am using CR2 files. Would it
> be different if I used DNG files? I want to be able to make
> non-destructive modifications in camera raw and then stitch the
> images without having to go through a TIFF version. Will this be
Most likely not (although Joost made several things possible I never
thought they will come true).
PTGui uses dcraw for RAW conversion. dcraw is the mother of all
universal raw converters in terms of decoding the RAW image file and
there is where it's qualities are. Unfortunately it is not so good in
the post processing part, where the other RAW converters have their
strength. Many of the things ACR, Bibble, RAW Therapee, Silkypix or the
others do can not be done with dcraw.
Why don't you want to go through the TIFF version? You can delete it
once your panorama is stitched. You can do this even automatically using
a shell script.
The same subject was discussed in depth in those two threads:
>you can use raw files, but it doesn't apply the modified exposure
>parameters from the xmp sidecar file.
Correct. PTGui's RAW file support isn't meant to be a replacement for
high-level RAW processors, and because of the proprietary nature of
all third-party 'sidecar' files it doesn't read instructions from
those tools either.
This feature works as designed and some are finding it very useful -
but it isn't for everyone. If you want processing control of your RAW
files then keep using your current RAW -> TIFF workflow.
> So here is a novel thought. I wonder if you could make PTGui output a
> CR2 or DNG file so that you conserve as much data as possible for ACR
> manipulation after stitching. I wonder if that would have any benefit
> over outputing a PSD or TIF and running through ACR?
Most probably not. You have no masked layers in a DNG, hence you won't
be able to save "blended and layers" in a single file. You can't do CA
correction on a ready stitched panorama.
This would leave white balance correction and highlight restoration
(something most RAW converters do silently) as last benefits of doing
RAW conversion after stitching.
However, PTGui pro has a white balance tool itself (on exposure tab) and
highlight restoration probably isn't necessary if you shoot bracketed
and use PTGui pro HDR functionality. And if you use an external RAW
converter you'll certainly use it's batch functionality to get all
images of a panorama processed the same.
BTW.: There is a tutorial how to extract maximum dynamic range from RAW
into a single 16 bit TIFF file: