Hi
CA Madhu Ramaswamy, those are pretty good, I agree with you regarding aparture, for a single shot like these I would have narrowed the f/stop. As for flash, the rules change for a refraction shot, if you direct the flash straight at the drop the light around the drop will improve and the drop itself will become sharp but the image inside the drop (the refraction) will become faded and harder to see. Ideally the majority of the flash light should be on whatever the refraction is with only a little of the outer edge of the light skimming the droplet. However in your case your refraction is a large open scene so its not possible to light it all up with a flash. Tripod and longer shutterspeeds are your best options here. Let me know if you have any questions
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