Thanks Sakti-da, Mrudul & Deepak.

Trying to figure out reason for subject softness, got same comment on earlier crested lark image. So, surely not doing something right..

Here are my thoughts & would like to hear from this forum on improvements/ change in technique required :

1. Using center AF point for focus & recomposing, Could this be the issue..
2. Using back button focusing to avoid hunting of focus, Am I missing something here..
3. Hand holding & at 400 mm, there is some movement in field of view, could this be the reason..
4. Could there be some issue with the lens in locking focus, before or after AF point..

Look forward to hear from you ..

Regards/ Anil Kumar Verma