(Jeffery Small) wrote:
I thought I would post this to the digital group to see if there were any
Minolta or Sony users who used the UFRaw converter software with their raw
image files. I have been having serious problems and wanted to see if this
was observed by others. Here is my story.

Ubuntu 13.10 system running on an Asus U56E system
UFRaw ver. 0.19.2
Dcraw ver. 9.19.1
GIMP ver. 2.8.6
Darktable ver. 1.2.3
Shotwell ver. 0.15.0

When attempting to load Minolta (mrw) and Sony (arw) raw image files into
GIMP, the UFRaw plug-in is not properly processing them. The following
webpage has images which demonstrate the problem:

http://smallthoughts.com/photos/misc/GIMP/index.html

The raw files are being imported with distorted color, exposure and
contrast. However, as the additional images show, other programs such as
Darktable and Shotwell and the Minolta/Sony editing programs (on Windows)
are importing and displaying these raw files properly.

Has anyone else been experiencing similar problems with their raw files of
any type?

Typically UFRAW is configured to save the current
configuration as the default for the next image, which
means (with that option enabled) you must set all
configuration options each time UFRAW is started. Or
another way to put it, there is no standard set of
defaults that will always be somewhere close. If the
last image processed was way out in left field, the next
one will not even come close to looking right unless it
is also off into left field.

With the screen shots you are showing we can't tell
anything other than what "exposure" is set for. There
are two places where a gamma curve can be set, plus
slider options for gamma value and gamma linearity. (If
it is compiled in, you may also have a slider option for
"contrast".) Any of those, with odd defaults, might be
the cause of the way the RGB image is being produced.

There are a number of ways, if you need a standard
default configuration, to accomplish that.

You could configure UFRAW to have one preset default
configuration used for every image. Sounds good, but in
practice that will cost a huge amount of processing time
unless you actually do RAW conversions one at a time
(for example using UFRAW as a plugin to GIMP to
preprocess individual images).

The most efficient workflow is usually invoking UFRAW
interactively on a directory full of RAW files, and
writing only the "ID" file for each while using it
interactively. When finished with all of the RAW files
UFRAW is then invoked as a batch process to produce the
RGB output files (while you can then take a coffee break
or whatever).

At the beginning of the interactive session every
configuration option is set as desired, and the
configuration for each image is the default for the
next.

--
Floyd L. Davidson http://www.apaflo.com/
Ukpeagvik (Barrow, Alaska)