4K Tele effect?

[MikeSD]

In still photography, one can get telephoto effect by cropping.

I assume is same for video. But is making a video at 4k and then cropping down (not down converting), to 1080 a reasonable way of going zoom effect.

I have an Osmo, that doesn't have tele lenses. I'm just wondering if I can get useful video if I use 4k, then in Adobe Pemier to zoom in so that the video is 1080.

Would that produce video anywhere near videoing in 1080, with a the equivalent tele, which doesnt exist?

[ChapmanDolly]

I don't know about Premiere, but in Resolve you can do a dynamic zoom which gives the effect of zooming in. Remember though, doing it this way will not give the forshortening of the image that a zoom lens gives. If you are on a 4k timeline, yes enlarging and cropping the image will reduce its' resolution downwards, but you will still be on a 4k timeline so you could render the whole video out in HD.

[johnmeyer]

In still photography, one can get telephoto effect by cropping.

I assume is same for video. But is making a video at 4k and then cropping down (not down converting), to 1080 a reasonable way of going zoom effect.

I have an Osmo, that doesn't have tele lenses. I'm just wondering if I can get useful video if I use 4k, then in Adobe Pemier to zoom in so that the video is 1080.

Would that produce video anywhere near videoing in 1080, with a the equivalent tele, which doesnt exist?

Cropping (which is what you are describing) does not produce the same result as using a telephoto. Cropping merely makes the image larger/closer, but a telephoto lens completely changes the size relationships between the foreground and background, and also can (depending the aperture) change the relative focus of foreground and background objects (selective focus). So, if your intent is to achieve the look of a telephoto, you will have to put foreground and background objects on one or more layers in your photo editing program, and then change the focus and relative size of those different layers.

This was done to great effect in the movie "The Kid Stays In The Picture" where, in addition to doing what I described, the director animated the results à la Ken Burns.

[MikeSD]

I am only interested in making the subject appear closer, with about the same image quality of the subject. I'm not too worried about background objects.

I'm trying to get a little more telephoto effect from my osmo pocket. It's pretty good as it is but it would be a little better, for my use, if not as wide angle. And for cases where I dont need 4k, cropping and making it 1080 might solve that problem.

Maybe I'll have to make a 1080 video and compare it to a cropped 4k video. I wont be able to compare a 1080 tele since no lens exists but I might be able to compare video quality.

[jagabo]

Of course the crop won't be the same quality as using a zoom lens and shooting at the same resolution. Whether you can see the difference or not depends on the size and resolution of the screen and from how far away you view it.

[andkar]

Cropping and zooming does the same thing with the perspective.

[Cornucopia]

*IF* you stayed at the same distance relative to your subject, and ONLY adjusted the zoom setting, because of the magnification, it would have the same effect as enlargement+crop.

*IF* you started with a 1080p timeline and put a 4k asset in and did the zoom via the editor (instead of via the camera), it WOULD have the same effect, with little-to-no change in apparent resolution. If your timeline is 4k however, you will notice a drop in resolution.

The caveats mentioned earlier pertaining to focus & foreground/background size relationships are directly due to the inherent change in distance, NOT necessarily the actual change in zoom setting (though one usually forces the issue for the other).

Scott