What would be the advantage to not shooting video in 4K, but using 2.7K instead? Won't the 4K video be of a higher quality?

Depends on so many things... Of course 4k is better quality but at the same time it's more disc space consuming and more difficult to edit if you don't have powerful computer.

4k advantages: more possibilities in post such as cropping up to 1/4 of the picture, better look even if downscaling to 1080p, easier to stabilize the picture in post, many others

4k disadvantages: size of the file is 4 times bigger than Full HD, and about 150% bigger than 2.7 k, require powerful edit station for smoothly handling 4k,

Generally before You choose resolution ask yourself what will you do with this file afterwards? Do you edit in professional way using professional software, are you familiar with adding effects, color grading etc? Remember that not even 10% of people are able to display 4k  which means for now it is more about getting more option and possibilities in postproduction than presenting content in 4k to others. Remember also than most of the content is nowadays presents via internet, being seen on mobiles/tablets - most of filmmakers still sticks to the full HD when presenting final results and shooting in 4k only for more flexibility in post.

PopArt Posted at 2016-1-3 10:00
Depends on so many things... Of course 4k is better quality but at the same time it's more disc spac ...

Great answer!  The other thing that bothers me about 4K and 2.7K is that the FPS is max 30.   I still generally love shooting in 1080 60fps...gives a much smoother final if your flying with a lot of fast turns or sideways shooting.  Just my $.02.

Hello,
I wake up this topic ...
I read 2.7k uses less compression, thus offers more "dynamics" or "depth" compared to 4k : true ?

bahamasboy@aol. Posted at 2016-1-3 11:49
Great answer!  The other thing that bothers me about 4K and 2.7K is that the FPS is max 30.   I still generally love shooting in 1080 60fps...gives a much smoother final if your flying with a lot of fast turns or sideways shooting.  Just my $.02.

read about ND filters. If you can keep double shutter speed again FPS so 30 FPS video can be supersmooth.

M_str Posted at 2017-6-1 03:40
Hello,
I wake up this topic ...
I read 2.7k uses less compression, thus offers more "dynamics" or "depth" compared to 4k : true ?

It depends on what codec is used and the ratio. Some codecs will limit the dynamic range of color etc. The ratio of the footage can change the PPI.

Actually, from the beginning, disk space is not a problem so I use 4k.  But, I read somewhere 2.7k might be better ...  explaining my interest for this topic

PopArt Posted at 2016-1-3 08:00
Depends on so many things... Of course 4k is better quality but at the same time it's more disc space consuming and more difficult to edit if you don't have powerful computer.

4k advantages: more possibilities in post such as cropping up to 1/4 of the picture, better look even if downscaling to 1080p, easier to stabilize the picture in post, many others

- most of filmmakers still sticks to the full HD when presenting final results and shooting in 4k only for more flexibility in post.

That summed it up right there!

I have read as well as seen videos of people saying that the 2.7K is more flexible in post with grading (faster and easier with less macro blocking) as well as less of the water color blurring compression artifacts that I seem to also get in C4K 24fps.   So I’m going to try try it with the Osmo + for a while.   Also even when choosing D-LOG I still lower contrast to -3 in camera, sharpness -2...  I leave color at 0.  What I have read but have NOT confirmed is that yes 4K is at 60 mbps and 2.7K is  reportedly at 45 mbps.      Also the tests I have seen where static shots.. I use my Osmo very mobile.   So no idea if the 45mbps is correct for 2.7K or that it hasn’t been changed with the updates that happened over the last year.   But again I’ll try the 2.7K for a while.

2.7K will use less storage on importing the files and the Micro SD card during flight and less time uploading edited files to social media etc. Plus the difference in resolution is minor but at closer range the detail in 4K is noticeable in comparison.