Hey guys, thanks a lot for your feed back. You're definitely right.
For sure cap will never take off .. it's just something what I wanted to see, no matter if it can't happen in real life. Lot's of things can't happen in real life

that's why we are here and not on photography forum

but for sure you're right, in reality it will stay on it's place . .at least until it hits the ground. Bottle shell feels thinner ? hmm .. I was using technical drawing of a shell

but that's a good thing to consider for future modeling .. you're right, it probably would look more interesting if it would be a bit more massive.
Reflectance has tinting ? .. for sure .. usually we see white reflectance only when this is the color (or temperature) of our light sources (light panels in my case) .. I was using 5000K D50 .. (I mean HDR image of it) which has slightly warm tint

but this is very good and useful point … thanks a lot for this … Maybe I should consider using neutral white to gain more believable look .. anyway a lot of things to think about

And yeah, there are some edgy feel on a closeup .. I know … I was planning only animation .. but afterwards I decided to try a close up .. and yeah .. it turned out that there were not enough subdivision .. a bit sad, but .. well that's my fault.
Thanks again for your feedback, that's what I wanted to hear, you guys are helping a lot, please keep doing it

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