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Comment by lucb1e | Hacker News Reader

Note this is not aerial imagery shot from an aircraft with an Apple phone, this is someone with an Apple phone on their head cycling around the neighborhood and then viewing the 3d model from above.

No less cool, but I was rather confused for a lot of the article, wondering what in the world the range on this sensor is (usually you get a few meters on normal-priced sensors, not hundreds of meters, and the picture showed entire streets being captured). The article actually mentions the maximum range is 5 metres after you set it to low confidence.

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Thanks for this - I'll update it to try and be more clear!

This capture was just holding an iPhone in my hand - but you can place it on the front of a bicycle too.

The Apple ARKit part handles the SLAM [1] of fusing the camera/LiDAR/gyro and possibly GPS.

[1]: https://en.wikipedia.org/wiki/Simultaneous_localization_and_...

> I'll update it to try and be more clear!

Not an issue of yours, it's all a matter of context -- and how closely one reads the article while trying to get an idea of what it's about. I just happen to be in the OSM ecosystem deep enough to be very familiar with the word aerial (as opposed to other types of area photographies), but not deep enough into the Apple sphere to know the capabilities of these devices and realize what the title clearly must mean. It might just be a me-issue :)

This is really cool, thanks for sharing.

Do you know the functional limit of the iPhone’s LiDAR? Ie: could I strap my Pro to my old DJI drone and create some photogrammetry of my house or whatever?

> could I strap my Pro to my old DJI drone and create some photogrammetry of my house or whatever?

Yep that should be possible - as long as you flow below 5 metres though!

If you have a drone and are somewhere that is legal & safe to fly, photogrammetry (3d model from just visual photos) will likely give a better result than relying on the iPhone LiDAR stitching.

Set the drone image self timer to 2 seconds, fly around for a bit and then upload all the photos into WebODM: https://opendronemap.org/webodm/

You can run it on your local machine (see instructions in blog post) or hosted for a fee. It creates brilliant models and is a lot of fun!

I've never gotten photogrammetry from a drone to work properly. Frankly the headache is just not work it in my opinion, especially since it usually entails flying low enough to annoy your neighbors.

I’ve personally gotten some pretty great (in my opinion) 3D models with just a DJI mini 2 and realitycapture

That's not my experience at all - even just driving the drone in a straight line with a 2 second (repating) self timer on I get great models processing in WebODM with the default settings.

> it usually entails flying low enough to annoy your neighbors

In my experience the higher the better - you can get a really nice model from 120m (legal limit in Australia).

You can also just use the photos from the drone but they won’t be as accurate or precise but it’s still worked for me pretty well

I would suggest "birds-eye" or something similar. That's sufficiently ambiguous that the source doesn't matter - e.g. an ortho is essentially a top-down view of a 3D-modelled surface. I guess most people outside GIS/Remote Sensing are unfamiliar with the terminology though.

The problem (I guess) is that aerial/satellite/orthorectified are not equivalent.

> The problem (I guess) is that aerial/satellite/orthorectified are not equivalent.

Yep I agree - I would call it orthorectified georeferenced imagery but unless you're in the GIS/OSM space you probably don't know what that means. I agree that "birds-eye" would have been a good alternative.

Satellite imagery is technically incorrect whether it's from a iPhone or a plane but that's what most people call it and know it by. (I love this thread on how "satellite" almost became known as "bird mode": https://twitter.com/btaylor/status/1099370126678253569)

I chose aerial imagery as an in-between - understandable to everyone, still not correct but less incorrect than satellite imagery.

>The iPhone LiDAR sensor has 5 metres max range, so you’ll need to walk around

I thought he was walking around. The bicycle helmet thing was an alternative to this method.

But yes, the article definitely needs a more detailed section on the practical aspect of recording.

I thought it was more cool, being able to generate such images than taking it from an aircraft/drone.

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