======Infrared======

Discussion about this tutorial on [[http://www.flickr.com/groups/photivo/discuss/72157626283356891/|Flickr]].

This is a basic tutorial about how to process pictures in Photivo that were taken with an infrared filter. The image you see was taken with a regular Pentax K20 and Hoya R72 filter.

Right after opening an infrared picture it has a very severe red/brown tint. So, the first thing I do is getting the spot white balance on some leaves in the image (because white leaves in IR images tend to look good); here I used the lawn. This preview is in tab mode, so no filters in the following tabs are applied, besides the contrast corrections in the **Output** tab.\\
[[http://www.photivo.org/_media/tutorials/infrared/photivo_001.jpg|{{:tutorials:infrared:photivo_thumb_001.jpg?nolink| }}]]

In the **Geometry** tab I corrected the rotation and perspective to get the building straight. That made black borders appear, so I needed to crop and then resize to the screen shot resolution. In the preview you see the crop tool in action.\\
[[http://www.photivo.org/_media/tutorials/infrared/photivo_002.jpg|{{:tutorials:infrared:photivo_thumb_002.jpg?nolink| }}]]

Now a really essential step follows in the **RGB** tab. We have to switch the red and the blue channel with the channel mixer. You can do this manually or by opening the **IR_Channelswitch** preset like I did. Then **Brighten** just does its job... \\
[[http://www.photivo.org/_media/tutorials/infrared/photivo_003.jpg|{{:tutorials:infrared:photivo_thumb_003.jpg?nolink| }}]]

Since it still looks rather dull, we need some contrast. I chose the two **Texture contrast** tools with large scale, but you should of course also experiment with the other contrast tools till you like the look.\\
[[http://www.photivo.org/_media/tutorials/infrared/photivo_004.jpg|{{:tutorials:infrared:photivo_thumb_004.jpg?nolink| }}]]

Processing in the **Sharpen/Noise** tab is always highly subjective. I chose the **Luminance Denoise Curve** to get cleaner blue values (curve above midline) and increase structure in the other values (curve below midline). Furthermore to get some more pixel contrast I used the microcontrast of the **Gradient Sharpen** tool.\\
[[http://www.photivo.org/_media/tutorials/infrared/photivo_005.jpg|{{:tutorials:infrared:photivo_thumb_005.jpg?nolink| }}]]

Just a little more color with the **Saturation Curve** in adaptive mode and a weak vignette to keep the viewers focus.\\
[[http://www.photivo.org/_media/tutorials/infrared/photivo_006.jpg|{{:tutorials:infrared:photivo_thumb_006.jpg?nolink| }}]]

Here’s the picture after all processing, including the contrast setting on the **Output** tab for completeness. No filters are active on the **EyeCandy** tab. I hope you also consider this a solid IR picture.\\
[[http://www.photivo.org/_media/tutorials/infrared/photivo_007.jpg|{{:tutorials:infrared:photivo_thumb_007.jpg?nolink| }}]]

However, personally I would not stop here. I like it a bit more dreamy and unreal. So, here is my final version. The filters differ only on the last three tabs. The screenshot uses the **active tools** view (rightmost button below the histogram) to to give an overview of all active tools. Have fun while playing with Photivo to get your desired look :-)\\
[[http://www.photivo.org/_media/tutorials/infrared/photivo_009.jpg|{{:tutorials:infrared:photivo_thumb_009.jpg?nolink| }}]]