Awesome, any breakdowns?
Hi ,
To produce these large 3D models, we use a mix of in-house, open-source and commercial processing software, as well as a strategic aerial acquisition technique using helicopter platforms and a capture system based on DSLRs coupled with IMU and GPS. We’ve captured about 6500 photographs to produce this 3D city model.
I work for a 3D mapping company and one of our core service is the capture and generation of entire 3D cities models. you can check out some example here https://www.youtube.com/user/Aerometrex.
We usually provide our clients with the data integrated in to dedicated 3D GIS software with virtually no limit to the size of the datasets (we’ve integrated 3D city models up to 30 GB with up to 8 LoD without any issues).
In UE4, it is a new concept as the Engine is focused on optimized data and not unique large 3D models.
To create this level I first created a a heightmap based on a Digital Elevation Model and textured it with aerial imagery as background map.
The challenge was in the integration of the 3D model.
We can output our data into FBX tiles (100m x100m) with simple LoD structure (in this case we can only use 4 LoD due to the limitation of UE4).
Using 3DS Max, we create a unique FBX tiles with embedded texture and LoD.
After that we just load all the tiles at once into UE4 (for this example, we had 142 FBX).
There are still a few issues to resolve such as the specular reflection of the model. UE4 doesn’t offer the possibility to bulk modify materials and so fare we would need to change all the 568 materials manually.
I find that the “cap holes” 3ds Max modifier is useful for cleaning up 3d scans, as is the “STL check” modifier.
You can use one Master Material and create instances from that and change only Albedo/Diffuse and Normal (+Metalness and Roughness if needed) in them 
Anyway, amazing work! 
Thanks!
my experience with UE4 is still limited. How do I associate a material instance to an existing material?
I though a mesh could only have one material associated to it.
Would you mind giving me a bit more details on that process, that would be very helpful?
I am guessing you did not create the 500+ material in UE4, and they were automatically generated by unreal during import. If so creating a master material and creating instance from it can as much time consuming as modifiying all 500+ materials.
To create a material instance you just right click a material and choose create material instance. To assosiate a matieral instance to master material, open the material instance and choose the master material in the properties, you can bulk edit the properties of the material instaces. But you cannot attach a regular material as an instance to a master material.
A mesh can have one material attached to it, unless you have material id assigned to polygons in a 3rd aprty application.
Btw love your channel, I am trying to do the same thing but more focused, I focus on smaller sites but do them with cm precision, I am testing pix4d and agisoft and pix4dmapper with an inspire 1 and UE4.
Hey guys, photogrammetry is still something new for me, but trying to get into it.
I have a camera Olympus E450, the thing is I don`t get a few things:
For how to utilize shot with HDR and grey balls? (are those important so?)
Also is it important to have a color checker for shooting?
How to handle with shadows, as I saw in Epic article, theyve used secret script, which removed all highlights on textures and made those solid, without no shadows (Any alternatives scripts to buy if Epic dont want to share it?)
Thank you in advance guys
A friend of mine, professional photographer, says it’s not about the camera but the lens being used.
Hello awesome people,
I gave a try to photogrammetry, which was awesome and i am attaching some rendered images below to show the quality of my work. BTW the site i have scanned is 200 years old RATH (kind of wagon attached to horses) which is made out of wood.
Equipments used : Camera - Nikon D7100 (50 mm lense, shutter speed 1/200, f/8, ISO200-400, Dim. - 6000*3000 , .NEF file, GPS on)
1 Tri-pod
Duration to take photos (476 Photos) - 4 Hours.
Software Used - Reality Capture Demo version ( as you can see model is not cleaned cause i am not able to export it to 3-D software )
I have a question related to scanning large architectural buildings for virtual tourism. I have around 10-15 sites to scan with high quality of details.
Using 360 camera with 4K recording and making 3D mesh out of it… will i be able to get high quality ? Mostly i am struggling in interior mapping
because of low light and congested space, will 360 camera will work ?
Is there any other method that i should try?
Taking pictures is an exhaustive work and there will be so many people around onsite. Keeping that in mind, recording 360 video @4K
while walking will solve my problem?
I am going to use** Drone** as well for exterior mapping. i am pretty sure there will be no problem in that.
Any suggestions or lead would be helpful for me.
Thanks
Rajat
I wouldn’t use a 360-degree camera, it’s likely to end up without enough resolution for the areas that you are focusing on.
Recently I tried out a program Pix4DMapper and so far it’s performed much better than any other program I’ve tried, I was using it on some shots from a movie and was actually able to get some 3D scans of interiors that provided me with some information that I could use to model them properly. You can possibly get some better results trying that program. But ultimately you’ll get the best results using many high resolution photos so that’s always going to be the same case.
Thanks for suggesting Pix4DMapper, I will try and get back you with samples in sometime.
Can i combine 360 photos and high res images together ? i just asking for speed up the process.
Hello again @darthviper107 Pix4D is great. it produced more natural colors than my previous test with reality capture. Pix4D took
1:16 Hrs ( initial Processing) 1:33 Hrs (Point Cloud &mesh) in Pix4D and in reality capture it took me around 1 hour.
My PC specs are i7-8700K, 64GB Ram, RTX 2080.
here is the link to experiment with Pix4d : https://www.youtube.com/watch?v=S3B9s29geII&feature=youtu.be
Any suggestions to get more quality out of Pix4D?
Thanks
Honestly there’s many reasons why some scans are better than others aside than strictly hardware. For example the wooden posts in the image below I made by taking photos in my backyard using my Galaxy S7 and then calculating the model using Agisoft Metashape.
There’s a lot of different variables that can influence the quality of photogrammetry, with that said, there’s also many different ways you can increase the quality of the end result.
In fact, I get phenomenal results from my smartphone because I also generate high fidelity normal information from the color map and then composite that info onto the normal map bakex from the high poly mesh. It yields much higher
level of fine detail.
Also, you have to consider the environment you’re photographing in. The less intense
the sunlight/artificial light and the shadows are, the better.
Reflections are also something to avoid if possible. There’s products called “dulling spray” that help mitigate an objects reflectiveness without really influence the physical detail.
Also if you find there’s not enough captured detail, I sometimes will do another scan of the finer detail, make that into a seamless material and composite that onto the model.
Image format also matters. Use RAW if possible. Any Android on 5.0+ has the option. Will help to eliminate highlights and shadows, and help eliminate noise without completely killing detail.