'splain me: 4k to 1080p

3d87c4 wrote on 1/14/2014, 4:51 PM

Sorry if this is too newb...I'll hang it out here and see what happens.

Problem: I ride my bike at night a couple of times a week and video the animals I encounter with a GoPro hero 2 in the medium setting. I've captured some fun critters, but the GoPro field of view is so wide they are pretty small in the image even if I zoom in Vegas.

Solution? I'm thinking a GoPro hero 3, shooting at 4K, would help a bit by increasing the number of pixels per critter.

Question(s): What's the workflow for inputting 4K video, zooming, and output 1080P? Is it simply a matter of doing the editing in 4K then rendering in 1080P? What does Vegas do if I set the project settings to 1080 then import 4K---resample, zoom, or?

Just gathering information...thanks

Comments

NormanPCN wrote on 1/14/2014, 5:12 PM

If you edit 4K and render to 1080, then your critters will be the same size in frame as if you captured them at 1080.

If you capture 4K, set your project to 1080 and render to 1080 you get the same effect as above. Vegas will resize the 4K to 1080 while you are editing. However, In this mode you can use pan/crop to get in closer. The 4K data is still there. If you cropped all the way down to 1080 on the short side, then you are still keeping the source resolution and quality. If you crop smaller than 1080, in a 1080 project, then Vegas will be resizing the data larger.

Mark_e wrote on 1/14/2014, 6:24 PM

Don't forget 4k is only 15fps on the hero 3 and 3+ it will be a bit choppy. 2.7k runs at 30fps and is really nice you just won't able to crop as much.
I'd hang on a bit lots of 4k stuff coming this year so gopro will have some competition!
I'm interested to see the specs of the panasonic action cam they announced a 4k version of that, might be interesting! ( or not :) )

3d87c4 wrote on 1/14/2014, 7:08 PM

Ooops...15fps could be a problem, the camera is helmet mounted so pretty shaky as-is.

Sounds like 4K is still a wait and see proposition.

musicvid10 wrote on 1/14/2014, 9:37 PM

Your idea is centered around cropping (not zooming) 4K to 1080, and rendering while maintaining native magnification; iow, changing the canvas to crop the image. The result is it will display on a 1080p screen cropped without degradation because it is not resized.

This is a tried and true technique, still is used in cropping1080->720. The "apparent" gain is not quite as great, but still usable. You would use Event Pan/Crop, filling the screen in a 1080p project to accomplish this. Experiment.

Mark_e wrote on 1/15/2014, 12:12 AM

Also I think the med and narrow fov options in the gopro are effectively doing that crop for you you can see that as you get less fisheye distortion as you go to narrow as it's cropping the middle. The downside is narrow is worse quality as it's pretty much just taking a raw sensor crop I think and you have less framing opportunities.