27.2.09

TMO = Tone Mapping Operator = Pengendali Peta Tona

taken from : http://qtpfsgui.wiki.sourceforge.net/Hints+&+Tips
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Single Raw file workflow

You can load directly a raw file in Qtpfsgui via the File->Load Hdr... menu item. Doing so you will be able to tonemap directly this single raw file. This means that there is no need to create different exposures in Ufraw from your raw file.
If you don't like what Qtpfsgui does with your raw file, or if you want to process you raw file before loading it in Qtpfsgui (white balance, color profile, and so on), you can use Ufraw to tweak the color settings of your raw file, and then save the result as a 16-bits tiff tile.
Just remember to save the result as a 16-bits file, or you'll lose some dynamic range in the process.

LDR post-processing

If you don't like the result of a specific tone mapping operator, please keep in mind that after the tone mapping step you can still use tools like GIMP to post process the resulting image. For example, you can still fix the brightness, change the gamma or the levels, and so on

Tone Mapping hints

In this section you can find all the hints reported by the Qtpfsgui community on flickr.
Even if these techniques can be thought as "recipes", they are not a silver bullet technique, your mileage may vary.

Mantiuk

This hint applies only to the versions of Qtpfsgui where, in the Mantiuk TMO, checking the "Contrast Equalization" checkbox disables the "Contrast Factor" slider (i.e. for all versions <= 1.9.1). [3] First image: tone-map the HDR with the Mantiuk TMO, contrast and saturation set to 2. Second image: tone-map the HDR with the Mantiuk TMO, "contrast equalization" checked, and saturation set to 0. Mix them (in GIMP for example): use the first image as background, and change layer settings (or apply filters) to the second. If you simply set its opacity to 50%, you get a good starting point, but you can try to set its layer mode to soft/hard light, or to blur it a little.

Fattal+Drago

Some users have reported [1] pleasant results combining in GIMP 2 LDRs: one obtained with Fattal and the other one with Drago.
Use Drago for the first layer and Fattal for the second in overlay mode (70% can be a good starting point). These values can be thought as a starting point, you can then go on tweaking the opacity value and the tone mapping parameters.
You can also put the Fattal image down as the master and then layer the Drago image on top in overlay mode with c.50% opacity [1].

Fattal+Mantiuk

Source: [3]
  • Tonemap with both Fattal and Mantiuk to produce two images of the same size.
  • Using GIMP, open the Fattal image and open a new layer
  • Paste the Mantiuk image into the new layer and anchor it.
  • Change layer mode to 'Soft Light'
  • Play around with opacities till image looks 'right' to you.

Fattal's size dependency

Fattal is one of the most popular TMOs out there. As other local TMOs, Fattal is cursed with size dependency, i.e. keeping the parameters fixed, the result depends with the size. One way to cope with this problem is to move down the color saturation slide and move up the beta [2].

[1] http://www.flickr.com/groups/qtpfsgui/discuss/72157600715644855/
[2] http://www.flickr.com/groups/qtpfsgui/discuss/72157604342240233/
[3] http://www.flickr.com/groups/qtpfsgui/discuss/72157604004134895/

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