cropping advice

[KIPAX]

So I know how to crop.. My question is

If I am using 4k video with output to 1920 fhd Should I work in 4k and reduce when rendering or set my work to 1920 using 4k

let me explain.. If I am working in 4k and crop in.. then thats 4k video reduced so will lose quality... But if i set my work area to 1920 then is all the 4k vid reduced then when i crop in that clip is reduced even more

Having trouble getting my head around it

would you work in 4k cropping in up to 50% when needed and then ender as 1920 and expect it all to look good?

 

[jamesianbriggs]

I recently did a project that was shot in 4K but which I ended up reducing to HD at the end because I wanted to incorporate quite a bit of archive stuff in that format.

With hindsight, I wish I'd set the project up as HD to start with because it allowed me to use the 4K footage to 'zoom in' on a number of shots i.e. most of the 4K was scaled to 50% to fit but some stuff I'd scale to 70% to create an artifical zoom. There was no visible change in quality when doing this.

 

[TimHughes]

So I know how to crop.. My question is

If I am using 4k video with output to 1920 fhd Should I work in 4k and reduce when rendering or set my work to 1920 using 4k

let me explain.. If I am working in 4k and crop in.. then thats 4k video reduced so will lose quality... But if i set my work area to 1920 then is all the 4k vid reduced then when i crop in that clip is reduced even more

Having trouble getting my head around it

would you work in 4k cropping in up to 50% when needed and then ender as 1920 and expect it all to look good?

I don't fully understand the question..... I'll have a try at answering....
If you shoot in 4k but only use an HD crop from that then you have not lost any resolution or quality if the final result is HD. To do this is quite a common practice to allow for some reframing and suchlike. However working in 4k uses a lot more disk space and needs more processing power than HD, so if the end result is going to be HD and you won't need to crop then shoot in HD and make your life easier.

Does this help?

 

[KIPAX]

I don't fully understand the question..... I'll have a try at answering....
If you shoot in 4k but only use an HD crop from that then you have not lost any resolution or quality if the final result is HD. To do this is quite a common practice to allow for some reframing and suchlike. However working in 4k uses a lot more disk space and needs more processing power than HD, so if the end result is going to be HD and you won't need to crop then shoot in HD and make your life easier.

Does this help?

heyup..yeagh sorry i tend to type as I think

The whole point is I do need to crop So i will always be shooting 4k and output HD

edit in 4k and crop in 4k

edit in HD and crop in HD

I guess my question is. if I edit in HD and crop.. wont that lose some quality as I am cropping HD

If I edit in 4k and crop 50% then I still have HD quality

If I edit in HD and then crop 50% havent i got 50% less quality ?

 

[Adam-G]

I think I'm grasping what you're getting at.

Dependent on the software you use, yes, if you take your 4K footage down to 1080p pre-crop, then you will be sub Full HD (1080p) resolution with any crop you make to the 1080p footage resulting in sub HD output when rendered.

Some editing software allows you to temporarily reduce detail and then restore it pre-render. I use Da Vinci Resolve where I shoot in 6K, edit my timeline in 1080p so it runs super smooth, then I restore the resolution and output at a supersampled 4K for best quality.

 

[KIPAX]

Am using Vegas Pro 17.. SO best to edit in 4k then and when finished render HD

I set RESAMPLE MODE to DISABLE .. Options are SMART & FORCE should I be using one of those or am i on the wrong track ?

 

[Adam-G]

Am using Vegas Pro 17.. SO best to edit in 4k then and when finished render HD

I set RESAMPLE MODE to DISABLE .. Options are SMART & FORCE should I be using one of those or am i on the wrong track ?

I've had a quick look and Resample mode seems to be some kind of frame interpolation that blends footage of different framerates to be consistent. If you've ever seen a TV with motion smoothing mode - that's doing a similar thing. It never looks anything less than awful so you're definitely right to keep that off I think.

Just keep a consistent framerate on your timeline for best results.

 

[sk66]

Am using Vegas Pro 17.. SO best to edit in 4k then and when finished render HD

With the Vegas software it doesn't matter how you set up the project... any video imported remains at its' original resolution until final render. IMO you will be better off setting it up as HD from the start.

 

[KIPAX]

With the Vegas software it doesn't matter how you set up the project... any video imported remains at its' original resolution until final render. IMO you will be better off setting it up as HD from the start.

I cans set the project to whatever size I want.. IF I set th HD from the start... when I crop in wont i be getting sub HD though ?

 

[sk66]

I cans set the project to whatever size I want.. IF I set th HD from the start... when I crop in wont i be getting sub HD though ?

No, the video is imported in its original resolution (4k); it isn't resampled (downscaled) until the final video is rendered. While working with the 4k in an HD project it is placed in the timeline at 50% zoom/view by default. Doing what you are wanting to do is very common (using 4k for zoom/pan in HD project), this behavior allows you to do that seamlessly. Premier and Resolve do the same.

Some (less professional) software might downscale the 4k during import instead, and that would cause the issue you are concerned with... but I don't know of one offhand; even iMovie allows 4k/1080 mix during editing.

 

[KIPAX]

No, the video is imported in its original resolution (4k); it isn't resampled (downscaled) until the final video is rendered. While working with the 4k in an HD project it is placed in the timeline at 50% zoom/view by default. Doing what you are wanting to do is very common (using 4k for zoom/pan in HD project), this behavior allows you to do that seamlessly. Premier and Resolve do the same.

Some (less professional) software might downscale the 4k during import instead, and that would cause the issue you are concerned with... but I don't know of one offhand; even iMovie allows 4k/1080 mix during editing.

CHEERS Right so i can go forward with confidence... set work area to same as output without losing quality ..ta