Its going to be really hard to respond to this question unless we can see a screenshot of what your interface or site currently looks like. However here are some reasons as to why you are not getting a 100% right to left F shaped pattern for your site:
- Your interface might not be totally right justified as explained by this article :
Our usability studies in countries that read right-to-left found the
same general pattern of increased attention to a line's beginning.
Obviously, in those languages, the beginning would be the right side
of the text. Even so, we wouldn't necessarily find a mirror image of
the above chart from eyetracking studies carried out on, say, Arabic
or Hebrew sites.
The reason is that sites in right-to-left languages don't always
employ a mirror image of traditional left-to-right layouts. See, for
example, the following screenshots from the Dubai newspaper Emarat Al
Youm and the Israeli newspaper Haaretz :
Emarat Al Youm is a true right-justified site. In contrast, Haaretz uses right-justified text, but still has a navigation bar to the left.
So, an eyetracking study's results for Haaretz might be more complex
than simply flipping the pattern we see on English-language sites.
Another interesting findings was that irrespective of the visual patterns or attention, visual
attention of all thesubjects was directed to the image of
Masjid-u-Nabawiwhich can be interpreted as attention influenced by
the cultural impact of the object of interest on the users.
- Another reason which is again mentioned in the above mentioned article is perhaps the influence of white space as mentioned below
Visual Patterns also showed how white spaces aided the users in reading
the text with least hindrance of the multimedia content. Figure 8
clearly shows a smoothreading pattern within areas of content and
longer sac-cades across white space that separates content areas
without any distarctions in the reading
- Another interesting thing which is called out in the article is that RTL languages dont exactly follow the standard F shaped reading pattern and often show a number of different reading patterns namely the Triangular and Zigzag pattern as shown below :
In a right-to-left layout, it was interesting to find z-shapedpatterns
in which viewers start with text then examine themultimedia content at
points in time in which the audio ac-companying the video or animation
or video emphasizes apoint with tone. Other instances of switching
between text and multimedia would be when animation is detected
byfoveal vision of viewers. Patterns showing brief examina-tions of
these areas are in line with the findings of  inwhich they have
shown that viewers struggle to ignore inter-face elements that are
animated and consequently exhibitincreased cognitive effort in
concentrating on the text whichis exhibited by intense fixation.
Visual patterns of triangular shapes were observed across the
eLearning interface. As shown in Figure 2 & 3the subject’s attention
alternated between the navigation,text and multimedia
Another visual patterns found in the Arabic interfacesare zig-zag
patterns. In this patterns, the reader startsfrom the right and
continue to the left then a little downand back to the right before
starting the another horizon-tal movement to the left again, which may
be because of the difference in the direction of Arabic scripts. Figure
9 shows the zig-zag visual pattern observed in the advertising study
All of this said, Philips answer is also spot on since there might be a number of users who are not Right to left language users and hence might start their standard scanning pattern from left to right with a standard F shaped pattern.