Photogrammetry is an amazing technology that lets you create 3D models of objects just by taking photos! I've been heavily researching and experimenting with it in the last few months in the process of writing my Instructables 3D Scanning Class and I wanted to make something simple from one of my scans. Of all the things I tried scanning, this starfish was one of the most successful models, and I thought it would make a nice pair of earrings.
Being able capture objects from reality and bring them into the digital realm is a really exciting prospect for anyone who works in 3D modeling. The possibilities of what you can create using this technology are really endless, and the fact that you no longer need a fancy 3D scanner makes the process accessible to almost anyone with a phone camera!
I this Instructable I'll give you an overview of the process I used to create these earrings as an example of one simple application of photogrammetry for design. I'll show you how I shot my photos and introduce you to a program called ReMake that will magically compile these photos into a 3D model in the cloud.
For a much more in-depth examination of photogrammetry and ReMake, check out my 3D Scanning Class, free for all members!
Thanks so much to the beautiful Alana Black for agreeing to model these earrings for me :)
Also, the design of these earrings was very inspired by the amazing work of Electric Candy Couture.
Step 1: Supplies
Capturing good scans with photogrammetry is mostly about technique, not fancy equipment or supplies, but you will need a few basic things. If you know what you're doing, you can get some pretty good 3D captures with a minimum of equipment. But in certain situations having some nicer gear will go a long way.
You will absolutley need:
- Camera (anything from a phone camera to a fancy DSLR)
- Autodesk ReMake (or another 3D capture program): ReMake pro is free for 15 days, free forever with limited functionality, $30/month for pro, or free for students
- Access to a computer with Windows 7, Mac OS X 10.9 or later and at least 12GB of RAM
- A three button mouse with a scroll wheel
- Access to a 3D printer or printing service (if you want to print your 3D model)
- Jewelry pliers
- Findings to assemble your jewelry (in my case, jump rings and earring posts)
Other useful equipment:
Step 2: Download Your Photogrammetry Software
There are a lot of software options on the market that will turn your photos into 3D models, but the Photogrammetry software I use is called ReMake.
You can try a 15 day trial of the pro version of ReMake for free, which lets you upload unlimited photos and create as many models as you want in that time. After that, you can keep using a free, limited version of the software which will still be great for most hobbyist applications, or you can purchase a pro version for $30/month or $300/year. ReMake is free for educators and students though!
To use ReMake, you will need to create a free Autodesk account. Go to https://accounts.autodesk.com/register and create a username and password. With this account you will also get 5GB of free cloud storage space that you will need to store the photo sets you upload to create 3D models.
The one downside is that ReMake is only available for Windows. But there are ways around this if you are a Mac user like me. You can install Windows on your Mac using Bootcamp so you start your computer with either a Mac or PC interface, or use Parallels to run both systems simultaneously. You can also subscribe to Frame for $10/month which will give you a virtual cloud based Windows desktop.
If you are already familiar with another software platform, or have free access to something other than ReMake, you can use what you are comfortable with!
Step 3: Find an Object to Scan
Because of the way photogrammetry works, some objects are easier to capture than others. Every situation will be different, but generally try to avoid:
- Very large objects
- Very small objects
- Objects in motion
- Shiny or transparent objects
- Featureless objects
- Overly complex objects with a lot of thin bits, undercuts, or pockets
I've tried quite a few objects with different methods, and the starfish I used for these earrings was one of the best scans I got. If you are planning to make a piece of jewelry with your scan, think about how your object will work for that application. How will it hang? If it is large, will it look good smaller? How will you attach it?
Step 4: Create a Scanning Set-Up
To photograph something for photogrammetric reconstruction, you need to take a series of overlapping photographs of an object from different angles. Photogrammetry software detects features on your object finding common points in overlapping pairs of photos which can be used to find the camera's placement in relation to the object for each photo.
There are two basic strategies when you are shooting for photogrammetry: you can either shoot by moving your camera around an object, or rotate the object while keeping your camera still. Because I have a tripod, some lights and a backdrop, I tend to prefer the second method, especially for small objects like the starfish. For more details about the two shooting strategies, check out the Shooting for Photogrammetry lesson of my free 3D Scanning Class.
When you shoot a rotating object, you need your background to be perfectly blank or featureless. This means you will need a black or white backdrop that is big enough to let you shoot your object from both high and low angles. Set up your lights on either side of your object from the front, adjusting them so they cast a diffused light and create an even background.
It's also a good idea to fixture your object so you can see all sides of it. To do this for my starfish, I stuck a stiff wire through a piece of wood and taped the wood to my lazy Susan. Then I positioned the lazy Susan under my black backdrop and poked a small hole so the wire could stick through. I drilled a small hole in one arm of the starfish and stuck it onto the wire so it was suspended in mid-air over the backdrop, but I could still turn it by reaching underneath and rotating the lazy Susan.
Step 5: Shoot Your Object
It can take quite a bit of finesse to get the right kind of photos to capture an object. In this sense, a large part of learning how to scan with photogrammetry is about learning basic photography and lighting technique, so I highly suggest also checking out audreyobscura'sPhotography Class for some great foundational information about camera operations and lighting.
Once you have your object fixtured, set up your camera on a tripod in front of your object at an angle that you think will capture some important details. Make sure your object is filling up most of your frame, but not being cropped anywhere. Remember you are going to be spinning your object, so if it's an odd shape the framing could change as it rotates. You need to shoot a lot of photos to capture an object well, anywhere from 20-250 depending on the size and complexity of your object.
Shoot one photo, then rotate your object very slightly on the turntable, about 5-15 degrees, and shoot another photo. Keep doing this all the way around until you are back to where you started.
Next, move your camera on your tripod to a higher or lower angle and repeat the same process.
Step 6: Upload Your Photos
When you think you have enough photos of your object, upload them onto your computer and take out any that are blurry or have other flaws. Now you can upload them and turn them into a model!
When you open up ReMake on your desktop, you will see a tab for your 'Dashboard' and 'Editor'. The Dashboard is where you will upload photos to be made into 3D models, and access the models you have already created. The Editor is where you view and edit your models once they've been reconstructed from your photos.
On the Dashboard, click on the ‘Photos’ icon under ‘Create 3D’. At this point you can choose to either create your model 'Online' or 'Offline'. Unless you have a very powerful computer, you always want to choose 'Online.' You’ll then be given an option to select photos from either your ‘Local Drive’ or Autodesk Cloud drive. My photos are on my computer, so I’m selecting ‘Local Drive’.
Browse to the folder with the photos of your object and open them. All the photos you selected will show up in a window. When you have all the photos you want, click the ‘Create Model’ button at the bottom of the page to upload your photos to the cloud.
Back on the Dashboard screen and you’ll see a thumbnail of your project under ‘My Cloud Drive’ at the bottom of the screen that shows the upload progress of your photos. Don’t click away from this screen until the upload is complete and has switched to ‘Waiting in Queue’. Once it has processed at least 1% in the queue, you can click away from this screen, but if you click away before that, your job will stop processing.
Now just wait for your model to be created which can take up to an hour.
Step 7: Check Out Your Model
Once a model has been created from your photos, you’ll get an email telling you that your file is ready. Now you get to see if your model was successful!
On the ReMake Dashboard, you will now see a thumbnail of your project under ‘My Cloud Drive’ that says ‘Ready to download’. Click on this and you will be able to save your model on your computer. Click on the model under 'My Computer' on the Dashboard to open it in the Editing environment.
When you first open your model, it will be shown to you with the color mapping, or 'texture' turned on. The model almost always looks best with the color layer turned on, so to actually tell how accurately your scan has captured the shape of your object, you need to turn off the color layer. On the bottom menu, click on the colored cube and you will see a menu with visualization options. Click on the grey cube to look at your model in 'Solid' view.
If your model has any visible flaws, you can usually fix and edit most of them with the ReMake editing tools, but if your model really doesn't look good, you might want to try re-shooting your photos.
To learn how to use all the great editing tools in ReMake (such as: slice, delete, fix holes, bridge gaps, smooth and sculpt) check out the Cleaning Up Your Model lesson of my 3D Scanning Class.
Step 8: Add Points of Attachment
If you want to make jewelry out of your scan, you'll need a way to attach earring posts or other findings. One way to do this is to export your model to a program like Meshmixer or Fusion360, but you can also use the editing tools in ReMake, and it's nice to not have to complicate your workflow.
For these earrings I wanted to attach several of the starfish in a chain in decreasing size so I needed to print some models with one hole and some with two.
To make a hole in the arm of the starfish, I first used the sculpt tool to pull and widen one of the ends of the arms so it could accommodate a hole.
Then I used the lasso selection tool to select all the way through both sides of the mesh and delete where I wanted a hole.
To close the edges of the hole, I used the bridge gaps tool to make bridges between the two sides at regular intervals around the hole.
Then I used the fill holes tool to fill in the spaces between the bridges.
I used the same process to create a hole on the opposite side of the starfish between the arms. I saved one version of the file with both holes, and one with only the hole between the arms.
Step 9: 3D Print
I printed my models on the Objet Connex 500 printers at Pier 9 which are UV cure resin printers. These printers print at a very high resolution which was great for something this small, but I think they would work on a lot of other printers too.
When I imported my files into the print software, I set them to the sizes I wanted for my earrings, making some smaller and some larger. I also tried printing them in both clear and white resin, and I like the way both looked in the end.
Step 10: Assemble
When I had printed and cleaned my parts, I assembled them into earrings using jump rings, earring posts and pliers.
I think the points of attachment on the prints are a little too fragile and I would probably make them a bit stronger next time but they have still held up fine so far!
Step 11: Wear!
I've been wearing my earrings a lot, especially the smaller ones, and getting quite a few compliments on them. But they look even better on my lovely housemate Alana, who was kind enough to model them for me :) Thanks Alana!
Now that I understand how to capture something with photogrammetry, I'm excited to make more pieces with this technique. I'm especially intrigued by the idea of combining models to create unique forms. If this Instructable has inspired you to to make a piece of jewelry with photogrammetry, please post an I made it below! And definitely check out my 3D Scanning Class for a lot more tips.