#370 ufraw/ufraw--batch ignore <Distortion Index='None'> tag

[Volker]

Steps to reproduce:

• Open a RAW file with UFRaw 0.19.2.

• Deactivate Lensfun lens distortion correction using Lens correction/Lens distortion/Model: None.

• Save a .ufraw file using Save/Create ID File/Only then Save.
  Section of the file reads:

  <Distortion Index='None'>
    <Model Label='PanoTools lens model'>
      <a>0.010714</a>
      <b>-0.021681</b>
      <c>0.004485</c>
    </Model>
  </Distortion>
  

so distortion correction should be deactivated.

• Reopen the .ufraw file with UFRaw.

Result: Model is on "PanoTools Lens Model" again, correction (re)enabled for ufraw and ufraw-batch.

Discussion: This is an undesired behaviour since it adds some softness and potential black borders around the image.

[Volker]

Addendum:

Precisely put, UFRaw only automatically (and errationally) looks up lens correction data,

• if the lens is known in the database,
• the "Lens correction/Lens" editbox is populated
• if you set "Lens correction/Lens distortion/Model" to "None",
• save the .ufraw recipe
• and reopen it with UFRaw.

An exemplary .ufraw recipe section looks like this:

    <LensfunAuto>no</LensfunAuto>
    <Lensfun>
      <LensModel>Nikon, Nikkor 105mm f/2.8D AF</LensModel>
      <Distortion Index='None'>
        <Model Label='PanoTools lens model'>
          <a>0.000000</a>
          <b>0.001420</b>
          <c>0.000000</c>
        </Model>
      </Distortion>
      <LensGeometry>Rectilinear</LensGeometry>
    </Lensfun>

, so you would expect "Lens correction/Lens distortion/Model" being "None" after reopening. In fact, it is "PanoTools lens model".

Here comes the fun part: If you manually remove the

<LensModel></LensModel>

entry from the .ufraw file, UFRaw opens it correctly with "Lens correction/Lens distortion/Model"="None"! In that case, it doesn't matter if

<LensfunAuto>no</LensfunAuto>

or

<LensfunAuto>yes</LensfunAuto>

is present in either .ufraw or .ufrawrc. Long story short:

<LensModel>

somehow takes priority over

<Distortion>

which it shouldn't. On a sidenote: ufraw-batch behaves the same.

[Jonathan Berry]

I had the same problem with UFRaw 0.20 on Fedora 20. I was trying to disable Chromatic Aberration correction (TCA) while keeping the distortion correction to be able to batch-process several images. I was able to get it to work by keeping the following in the .ufraw file:

  <LensfunAuto>no</LensfunAuto>
  <Lensfun>
    <Distortion Index='PanoTools lens model'>
      <Model Label='PanoTools lens model'>
        <a>0.003926</a>
        <b>-0.013819</b>
        <c>0.000000</c>
      </Model>
    </Distortion>
    <LensGeometry>Rectilinear</LensGeometry>
  </Lensfun>

On a side note, I was only disabling CA correction because it was causing red and blue spots to show up in the photos. Never seen that behavior before.