.cr2 floating-point-error from manual, unchipped Samyang no longer "academic"

[l_d_allan]

I un-installed the 1.9.x CodecRaw from Canon (32-bit) and installed the CodecPack from Microsoft that you helpfully provided a link to. Rebooted.

Problem with "floating point overflow" still exists on the desktop. Drat.

(Note: this problem is of somewhat academic interest to me, since I immediatly convert the .cr2 files to .dng's and proceed with .dng's. It only became visible because I wanted to "tell" the .cr2's from the manual Samyang about the f-stop "earlier" in the tool chain.)

The floating-point-overflow problem used to be academic, because I was able to use DngConverter to work and then use ExifToolGui.  You may recall it only happened with .cr2's when using a manual, unchipped Samyang lens.

However, now it isn't academic because the latest/greatest firmware from MagicLantern implements DUAL_ISO for better dynamic range from .cr2's.  They have a "package" of cr2hdr.zip that includes exiftool.exe and dcraw.exe.

Now that ExifToolGui isn't directly supported, I'm looking into climbing the learning curve for ExifTool itself.

Perhaps I'm being lazy, but is there some kind of script that would input a directory of .cr2 files (some manual Samyang that report 50.0 mm and nonsense FNumber, and other files from non-manual Canon EF lenses that report valid values), and accomplish something like ...
* For each image that reports 50.0mm focal length and FNumber of either 0 or -
** change "LensModel" to Samyang 14mm f2.8
** change "FNumber" to 8
** change "FocalLength" to 14mm

In effect, I'd really appreciate the capability of doing a "preset",

At least so far, my only "use case" is supplying the missing EXIF for a fully manual Samyang 14mm f2.8 lens.
LensModel: Samyang 14mm f2.8
FNumber: Usually f5.6 (reported as 0 or -)
FocalLength: 14mm (incorrectly reported as 50mm for some reason)

Is there a way to have a simple preset to fill-in this information for some/most/all files in a directory with minimal mouse/key-strokes?

I did get a reply from the post above, but it was "over my head" of this ExifToolGui newbie, and ExifTool pre-newbie.

[Phil Harvey]

is there some kind of script that would input a directory of .cr2 files (some manual Samyang that report 50.0 mm and nonsense FNumber, and other files from non-manual Canon EF lenses that report valid values), and accomplish something like ...
* For each image that reports 50.0mm focal length and FNumber of either 0 or -
** change "LensModel" to Samyang 14mm f2.8
** change "FNumber" to 8
** change "FocalLength" to 14mm

An ExifTool command to do this to an entire directory could look like this:

exiftool -if "$focallength#==50 and not $fnumber" -ext cr2 -lensmodel="Samyang 14mm f2.8" -fnumber=8 -focallength=14 DIR

where DIR is the name of the directory containing the images.

You could put this command in a .bat file and set DIR to %*, then drag and drop directories onto the .bat file icon to make this easier.

- Phil

[l_d_allan]

Thanks. Works well. There does end up a set of copies of the original, with something like file extension .cr2_original.

[Phil Harvey]

Add -overwrite_original if you don't want the backups.

- Phil