When I zoomed in 400% at 1080p, the video got grainy.  I would assume 400% zoom at 4K would look much better, if it was an option.

All Zoom is Digital, meaning there is no lens to zoom. I did a maximum zoom and it didn't look that bad!

videoeditman Posted at 11-20 18:19
All Zoom is Digital, meaning there is no lens to zoom. I did a maximum zoom and it didn't look that bad!

Ok, but I'd still like to know why higher zoom levels are limited to lower video resolution settings.

A simple explanation is that it is enlarging a specific area 4 times.  As a result the imperfection are amplified along with the size each pixel size. This ultimately results in lower quality image that is fuzzier in most cases.

I am sure there are much more detailed explanation that include many other factors associated with digital zoom. But it seemed like you were looking for a general explanation and not a technical one.

I think a more simple question might be:

Why is Zoom 4 x in 1080p but only 2 x in 4K.....

I am wondering the same

Here is an example of the 4 x Zoom at 1080p. Yes it gets a little less quality at full zoom but I think it is fine. Watch till you see the car round the corner at the bottom of the field

I never use higher than 1080p..... I dont think you need it and the files sizes it creates are just too big

https://www.amazon.co.uk/photos/ ... I8Kop1Rp3S6Eutu0DuB

JohnLietzke Posted at 11-20 19:33
A simple explanation is that it is enlarging a specific area 4 times.  As a result the imperfection are amplified along with the size each pixel size. This ultimately results in lower quality image that is fuzzier in most cases.

I am sure there are much more detailed explanation that include many other factors associated with digital zoom. But it seemed like you were looking for a general explanation and not a technical one.

Spot on

Sorry but the explanations given don't make sense.  If resolution is cut in half each time you zoom in 100%, then 4X zoom in 4K setting = 500p and 4X zoom in 1080p setting = 135p.  Are my calculations right?

JohnLietzke Posted at 11-20 19:33
A simple explanation is that it is enlarging a specific area 4 times.  As a result the imperfection are amplified along with the size each pixel size. This ultimately results in lower quality image that is fuzzier in most cases.

I am sure there are much more detailed explanation that include many other factors associated with digital zoom. But it seemed like you were looking for a general explanation and not a technical one.

A simple explanation is that it is enlarging a specific area 4 times.  As a result the imperfection are amplified along with the size each pixel size. This ultimately results in lower quality image that is fuzzier in most cases.

I couldn't have said it better.  

DowntownRDB Posted at 11-21 07:33
A simple explanation is that it is enlarging a specific area 4 times.  As a result the imperfection are amplified along with the size each pixel size. This ultimately results in lower quality image that is fuzzier in most cases.

I couldn't have said it better.

That would be a great explanation if my question was "why does quality drop when you zoom in?" but that wasn't the question.

My question is, if 400% zoom would look a alot better in the 4k setting (vs the 1080p setting), why isn't it available in the 4k setting?

There are two types of zoom on Mavic mini:

- when you are recording in 1080p (Full HD) mode there is losless zoom (2x - it based on changing of the are of the sensor where from information are taken - and because recording in 1080p covers whole sensor so there is still space to use smaller area of sensor and display it as 1080p resolution without need of multiplicating single pixels of sensor)  and lossy zoom (4x - where additionally each pixel of physical sensor has to be displayed as a few pixels of recording video)

- when you are recording in 4K - you can not take smaller part of physical sensor and strech it to 4K without loosing quality - in that mode video frame is covering already full sensor and zoom can be achieved only in lossy way - by taking smaller area of sensor and multiplicating pixels on the video frame.  

In my opinion only 2x zoom in 1080p has some sense because it doesn't breeng any reducion in video quality. 2x zoom in 4K and 4x zoom in 1080p can be atchieved in postproducion and doesnt bring any value if you want to edit that video later on computer.

fans427539f9 Posted at 11-21 08:02
There are two types of zoom on Mavic mini:

- when you are recording in 1080p (Full HD) mode there is losless zoom (2x - it based on changing of the are of the sensor where from information are taken - and because recording in 1080p covers whole sensor so there is still space to use smaller area of sensor and display it as 1080p resolution without need of multiplicating single pixels of sensor)  and lossy zoom (4x - where additionally each pixel of physical sensor has to be displayed as a few pixels of recording video)

Thanks, that's what I was trying to understand.  Another way to put it, the resolution at 4X zoom is a lot closer to 1080p than 4K and they left out 4X zoom from 4K because they don't want people to be shocked at the quality drop when they zoom in. (just a guess, might be wrong).

I think 4 x zoom in 1080 P is fine People are far to picky about picture quality...... No on has 4K eyes

trader6777 Posted at 11-21 08:11
Thanks, that's what I was trying to understand.  Another way to put it, the resolution at 4X zoom is a lot closer to 1080p than 4K and they left out 4X zoom from 4K because they don't want people to be shocked at the quality drop when they zoom in. (just a guess, might be wrong).

DJI may not include 4X digital zoom for 4K because the Mini's processor may not support the processing overhead that would be required to interpolate the cropped pixels.

4k Video on the Mini 2 uses us about 96% of the Cameras Sensor (4k being roughly equiv to 12mp when you shoot in 16:9)

If you take a 4k video frame and take the middle 50% of that frame you get what's essentially a 2x Digital Zoom (and 2k worth of image data).
If you take a 4K video frame and take the middle 25% of that frame it you get what's essentially a 4x Digital Zoom (and a 1k worth of image data from the middle).

Digital Zoom is essentially enlarging what's already there (it doesen't give you any quality or additional information). Sure DJI Could take that 1k of Data and upscale it to 4k video size however what would be the point? it would look no different than if you just watched it at 1k on a 4k monitor and let Windows Media Player (or whatever) scale it up for you, it would just waste processor time and disk space unless there ws some very good video processing on board the Mini 2 which I doubt

To illustrate I took the following 100x100 pixel image




And upscaled it to 4 times it's size. You will notice it's nowhere near as "crisp" as the original.

Bigplumbs Posted at 11-20 23:04
I think a more simple question might be:

Why is Zoom 4 x in 1080p but only 2 x in 4K.....

With question posed that way.  It is my understanding that the pixel density in 4K while much greater produces a sharper and clear image in native format does not translate well when zoomed in at greater than 2x.

It has to do with enlarging the pixel size and the sheer number of pixels which to the human eye produces lots of imperfections like blurry edges and artifacts.  It is much more noticeable in video than in a static image such as a photo.

I do not believe it is a processor issue per se but a limitation of 4K.  If the processor were to attempt correction it may not have the power or capability under that scenario which goes back to Occams Razors comment.  As the simplest explanation is ussually the correct explanation.

You will need the resolution to zoom.
(but note that you are only using a smaller part of the lens when zooming in, so you will lose detail on the lens resolving power that is not utilized to its fullest, though it is beter than zooming in post!)

JohnLietzke Posted at 11-21 09:29
With question posed that way.  It is my understanding that the pixel density in 4K while much greater produces a sharper and clear image in native format does not translate well when zoomed in at greater than 2x.

It has to do with enlarging the pixel size and the sheer number of pixels which to the human eye produces lots of imperfections like blurry edges and artifacts.  It is much more noticeable in video than in a static image such as a photo.

Also remember the zoom causes the portion of the lens that it uses to drop drastically.
This is making the image look 'soft' as it is not having as much resolving power (lens resolution) as when it could use the whole lens!

unpluggeduk Posted at 11-21 09:12
4k Video on the Mini 2 uses us about 96% of the Cameras Sensor (4k being roughly equiv to 12mp when you shoot in 16:9)

If you take a 4k video frame and take the middle 50% of that frame you get what's essentially a 2x Digital Zoom (and 2k worth of image data).

In FHD mode, there is a lot of 'zoom' you can make without losing pixels.
BUT
Also remember the zoom causes the portion of the lens that it uses to drop drastically.
This is making the image look 'soft' as it is not having as much resolving power (lens resolution) as when it could use the whole lens!

Montfrooij Posted at 11-21 12:42
Also remember the zoom causes the portion of the lens that it uses to drop drastically.
This is making the image look 'soft' as it is not having as much resolving power (lens resolution) as when it could use the whole lens!

Camera's are really not my thing, do you think would this also effect focus and cause a curvature distortion.  I read that in an other forum a while ago when there were complaints about no 4x zoom in 4K on the Air 2.  Or would this more of an issue on 48mp sensor like the Air 2 has?

JohnLietzke Posted at 11-21 13:27
Camera's are really not my thing, do you think would this also effect focus and cause a curvature distortion.  I read that in an other forum a while ago when there were complaints about no 4x zoom in 4K on the Air 2.  Or would this more of an issue on 48mp sensor like the Air 2 has?

I have not heard any details on that issue.

Montfrooij Posted at 11-21 12:42
Also remember the zoom causes the portion of the lens that it uses to drop drastically.
This is making the image look 'soft' as it is not having as much resolving power (lens resolution) as when it could use the whole lens!