Red free
How to use the Red Free Function.
The Red Free function will apply a Red Free filter to the entire image in the viewing area. This will result in a more defined and reflection free version of the vessels, which is especially important when analysing bulbar and lid redness.
Red Free Tool
Step 1: Select an image from the image's column on the left side, Figure 1.

Figure 1
Step 2: To activate this function simply click 'Red Free', Figure 2.

Figure 2
Step 3: To deactivate the filter simply click the 'Red Free' again.
Note:
Please take into account that the core functions (Bulbar, Lid, Staining) cannot be applied over the Red Free filter, as well as the other filters (Wratten, Enhance).
Additional tools like Annotate, Draw, and Ruler can be used while the Red Free filter is applied.