Which is better?

mavic_manzana · Apr 1, 2019

I am trying to distinguish people walking from long distances. I know shamefully little about optics. My question is "Which is better at resolving features at long distance- The Mavic 2 Zoom zoomed all the way or the Mavic 2 pro with the fancy camera?" Thanks for any advice!

Meta4 · Apr 1, 2019

mavic_manzana said:
"Which is better at resolving features at long distance- The Mavic 2 Zoom zoomed all the way or the Mavic 2 pro with the fancy camera?" Thanks for any advice!

The Mavic 2 zoom has a longer focal length when zoomed in.
However it's still not a telephoto lens and won't do much for you resolving detail at distance.
And because the zoom is a 12MP camera, you won't have as much detail to work with as the 20MP Mavic 2 gives you.
So ... neither is really great and perhaps either would be as good.

sar104 · Apr 1, 2019

In terms of native magnification (pixels per meter), factoring in both the difference in field of view and sensor size, the M2Z does a bit better when zoomed in, by a factor of 1.36.

mavic_manzana · Apr 1, 2019

Gads, you guys really know your stuff. Thanks a lot!

Brutka · Apr 1, 2019

sar104 said:
In terms of native magnification (pixels per meter), factoring in both the difference in field of view and sensor size, the M2Z does a bit better when zoomed in, by a factor of 1.36.

Can you please give the calculations here? Really interesting also to calculate that difference factor between 20mp pro and 12mp zoom without taking zoom in cosiderations

jwt873 · Apr 1, 2019

If you're only interested in what you see on your phone or tablet while flying and not the quality of the image, the Zoom has the advantage.

When the video mode is set to 1080P/30 or less, the Zoom has the ability to do 2X optical zoom plus 2X lossless digital zoom for an effective 4X focal length of 96mm.

(I posted the video below in another thread, but I can't find it now). As far as people walking a distance away, you can see a person walking out of the building in the center of the frame. You can see him unzoomed, and zoomed. (I was hovering at 300 feet and was 150 feet away from the building).

sar104 · Apr 1, 2019

Brutka said:
Can you please give the calculations here? Really interesting also to calculate that difference factor between 20mp pro and 12mp zoom without taking zoom in cosiderations

Sure. M2P has 77° FOV, 5472 × 3648 px. M2Z has 83° - 48° FOV, 4000 x 3000 px.

Those FOVs are diagonal, and so you need the diagonal px dimension, N, for the sensors (Pythagoras):

M2P: N = √(5472² + 3648²) = 6576

M2Z: N = √(4000² + 3000²) = 5000

At a distance d, the linear FOV of a camera, w, with angular FOV θ, is simply given by:

w = 2d.tan(θ/2)

and so the pixels per meter value is just N/w.

For the zoomed case, that gives:

M2P: N/w = 6576/( 2d.tan(77/2) = 4134/d

M2Z: N/w = 5000/( 2d.tan(48/2) = 5615/d

The ratio of those is 5615/4134 = 1.36.

If you substitute the unzoomed FOV for the M2Z then you can calculate the unzoomed comparison.

kilomikebravo · Apr 1, 2019

SAR, all I can say is, you certainly didn't forget your mathematics. Impressive to say the least.

For Mavic Manzana...

No doubt either will be about as good as the other for your specific need but me thinks in the long run, you'll be happier with the M2P and its higher resolution images. Just my $0.02.

sar104 · Apr 1, 2019

kilomikebravo said:
SAR, all I can say is, you certainly didn't forget your mathematics. Impressive to say the least.

For Mavic Manzana...

No doubt either will be about as good as the other for your specific need but me thinks in the long run, you'll be happier with the M2P and its higher resolution images. Just my $0.02.

That's just arithmetic. Well maybe with some very basic trigonometry. I guess it's easy to forget that many people don't use this kind of thing on a regular basis.

ZooCougar · Apr 1, 2019

I’m pretty sure SAR must design space ships or time machines. Impressive.

FormerMember07122019_2 · Apr 1, 2019

I’d like to hear from @CanadaDrone on this topic.

Mossiback · Apr 1, 2019

mavic_manzana said:
I am trying to distinguish people walking from long distances...

I will ask the key question; what do you consider long distances?

sar104 · Apr 1, 2019

ZooCougar said:
I’m pretty sure SAR must design space ships or time machines. Impressive.

No - but I did stay at a Holiday Inn Express last night.

brettbrandon · Apr 1, 2019

sar104 said:
No - but I did stay at a Holiday Inn Express last night.

That was a good laugh, thanks I needed it...

mavic_manzana · Apr 1, 2019

Mossiback said:
I will ask the key question; what do you consider long distances?

Far enough so they dont hear the drone. Like 2000 feet, maybe. Farther would be better.

sar104 · Apr 1, 2019

mavic_manzana said:
Far enough so they dont hear the drone. Like 2000 feet, maybe. Farther would be better.

Well then I'll refer you back to the equations in post #7. If you put d = 2000 ft then you get a resolution, with the M2Z zoomed in, of 2.8 px/ft. A person is going to be around 15 pixels by 3 pixels. Is that resolved enough?

CanadaDrone · Apr 1, 2019

mavic_manzana said:
I am trying to distinguish people walking from long distances. I know shamefully little about optics. My question is "Which is better at resolving features at long distance- The Mavic 2 Zoom zoomed all the way or the Mavic 2 pro with the fancy camera?" Thanks for any advice!

Neither are good at all for what you're trying to do, as both are pretty much built for the opposite usage scenario, but the M2Z would technically be better if resolving details at a distance is your only criteria. It can put slightly more pixel density on the subject from a farther distance with a still photo. For 4K video you're really splitting hairs, it's 40mm (M2P HQ mode) vs 48mm (M2Z zoomed in) equivalents, and the question then becomes if the better lens, better sensor, and better video quality from the M2P in HQ mode outweighs an extra 8mm of 'reach' you would get from the M2Z. Unless you are specifically buying the drone just for this purpose, I'd just get the Pro and be done with it.

Both of these drones would be pretty low on my list if picking out distinguishing features at 2000'+ was my goal.

Mossiback · Apr 1, 2019

mavic_manzana said:
Far enough so they dont hear the drone. Like 2000 feet, maybe. Farther would be better.

"Hearing the drone" is very subjective. At 2000 feet they probably would not hear it, but it depends on wind speed and direction, props being used, background noise, and their hearing ability. I can't hear my MP with MAS props at 1000 feet but my hearing isn't what it used to be. At 2000 feet it also will require adequate lighting but if all you are looking for is people walking without needing much detail, either platform will work. I will leave it up to owners of both to argue which is better.