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I heart OBJ


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7 hours ago, Claes Lundstrom said:

Though I would try the other formats supported by the iPhone scanner program. Besides OBJ, it also supports PLY and FBX. Not sure about FBX by this is what came out of the PLY version, when converted into a Digital Terrain model. The model was about 7 megs. The input as such was not as pretty as the OBJ, but the DTM thing working is a plus. Of course, it freaked out a little by the house and resting walls and where there was a steep rock wall, but not bad. Measurements seems t be right too. It only took a few minutes to get to this, plus the five to ten minutes it took to scan the site. Not bad for a phone? I even managed to include my feet here and there by scanning myself. 229710152_SurveybyiPhone2.thumb.jpg.7bfee93514a8d5af0d7e3ac2d91b1e9d.jpg

This is where cleaning the data and decimation in a suitable software can produce more manageable results.

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17 hours ago, E|FA said:

Just a heads up that this only works with Apple devices with a LiDAR sensor: iPhone 13 Pro, iPhone 13 Pro Max, iPhone 12 Pro, iPhone 12 Pro Max, and iPad Pro devices from 2020 and later.

 

Is there a difference scanning on an iPad compared to an iPhone does anybody know? I own neither nor have ever done so. Just wondering if any advantage to doing it on iPad in terms of range/speed/device getting hot/etc. I can't really justify getting an iPhone right now but could perhaps if it was an ipad...

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19 hours ago, bob cleaver said:

Hi All

I may have missed the use of an iPhone to scan real sites - is there a video of this operation so I can fully appreciate just how revolutionary I believe this is - I assume you are using a third party app ? 

There are many apps on Appstore doing this. I checked five or six and decided on Scaniverse as my personal favourite. It's also free, believe it or not.  Is it difficult to use? I bet you will get something reasonable good out of it in your first try. It's fairly similar to creating a movie. You get white and red stripes where it still misses data. Just move around with gentle movements and watch was happens on the screen. You need to practice a few times to know how to get the best result, but it's fun and easy. Skinning the model takes a few seconds, in any event less than a minute, after which you can look at the result on the screen in full 3D, including spinning and zooming. You can trim and rotate the model in the app, and even generate a movie or a still shot from any view. Then save the model if the preferred format. I have a Mac, so a quick Airdrop from the iPhone or iPad is the quickest way to export to the Mac. Takes seconds. OBJ gives the best rendering, whereas PLY works best for Digital terrain models. The Ply importer allows you to define the number of points to be used with a slider. Lower res may be good enough. It's a bit like using a well used piece of soap instead of a new one having sharp edges, or using a more or less blurry image to represent the shape. In VW, you import OBJ as OBJ and PLY files as a Point cloud. The sample model contained 469204 points.

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57 minutes ago, Tom W. said:

 

Is there a difference scanning on an iPad compared to an iPhone does anybody know? I own neither nor have ever done so. Just wondering if any advantage to doing it on iPad in terms of range/speed/device getting hot/etc. I can't really justify getting an iPhone right now but could perhaps if it was an ipad...

I think the liar is the same on iPhone 12, 13 Pro and iPad Pro. It's basically a matter of taste using a smaller or bigger screen vs how easy it is the bring it along at any give time. A smaller screen works fine for me tough. I have the bigger iPhone 13 Pro model.

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12 minutes ago, jeff prince said:


Processing is slightly faster on the phone, but this is negligible.  The ipad gets hotter due to its larger screen size and the processor working harder, but this is only noticed in temperatures over 75 F.  Either device can suffer from heat if kept in a case, removing them helps a lot.  I find the ipad is easier to hold, target, and view, the phone is a bit small for all the up/down and twisting moves performed during a scan, making it easier to drop when walking over uneven surfaces.  If I had to choose between them, I would pick the ipad for field work.  You can sketch, review PDFs, fly drones, and edit photos and video much easier on an ipad in the field as compared to the phone.  They will produce the same scanning results.

 

In terms of accuracy, realize that lidar scanning suffers the longer you scan.  Interiors of building are easy and fairly accurate, depending on the surfaces and how close you are to them (stay 3 feet or more away and it is stellar).  Doing individual rooms as separate scans is usually more accurate than wondering an entire building.

 

For exterior site features, it is more accurate and significantly faster than stretching tapes and using a level to collect data.  However, it’s far from perfect and cumulative error can displace objects in larger, complex scans by significant distances (over 6’), even when observing best practices under ideal conditions.  Even with these types of errors, it still proves to be more accurate than the old triangulation method given the same collection area.

 

So, great for capturing information quickly and getting started on a project, but far from a replacement of a survey grade scan or traditional point collection.  In regards to landscape architecture, I find the data enough to be productive until the proper survey is delivered.  I wouldn’t grade a site with the data from a lidar scan beyond conceptual.  I wouldn’t rely on it for location trees to be removed in a forested area where neighboring trees within 15 ‘ could be misidentified.  As long as you guard against these realities and don’t let the pace of a project lead to using it as the single source of truth, risk can be managed.  Putting a leash on an iPad is also a great way to manage risk 🙂

 

 

Good advice thank you. Just the kind of analysis I needed. Excellent

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Just found out from a recent grad that NSW Government in the area has made available all their point cloud map data for the whole state. Lower res than what we'd get from Drone flight which is both good and bad. 

 

Drone flights point clouds in urban areas have been a bit hit and miss you us. They tend to get confused by multiple building close together. It would be good if we could merge several sources.

 

Does anyone know of a way to embellish a point cloud with new photos or footage if you don't have the originals just the point cloud created from them. 

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