Reference image 3d modeling technique is to help modelers speed up their modeling process by drawing over their reference images or designs accurately. With just 5 to 10 minutes to insert a reference image before starting to model a 3D object, you speeds up your production by 5 times or more!
3D modeling using reference is important and critical to achieve good 3D geometry. However it is tedious and inefficient to model by comparing between the monitor screen and your printed design. Even if you have a huge monitor, it is still not easy to space out your monitor space just to view your reference image.
By modeling your object with a guided image behind, you can literally "trace out" your 3D object according to your reference image or design blueprint. Your model will be more accurate to the design (be it yours or client) and you take less time to model an object correct proportion compared to modeling by eyeballing.
Here are the 4 simple steps to reference image modeling:
Prepare your images with photoshop
Displaying your reference image, with correct scale and proportion.
Locking your reference image
Start your model!
Learn how to use reference image modeling from this video tutorial I've created using 3d software, Maya 2013.
*Note: This technique is not limited to Maya, all other 3d software are able to do reference image modeling too.
Step 1: Prepare your reference images
Find the blueprint image you wish to model. It can be any image or design you have created or downloaded from the web.
I've found an ironman character sheet from conceptart.org and I am only going to use the front and the side view to help me model. If you wish to put in all the other views, feel free to do so.
On each viewport, I only wish to see the respective view. For example, if I look at it from the left, we should only see the side view. This helps me by staying focused when I'm modeling.
When preparing the images, make sure that all the object's height and proportion is similar. This is important as it makes sure the design is consistent in proportion and accuracy.
Open the reference image file in Photoshop and make use of guidelines to help in marking out where you wish to crop the image.
Crop the images accordingly to the guidelines and name them respectively. E.g. Ironman_sideView.jpg, Ironman_frontView.jpg
Lastly, check and remember the dimension of your images. In my case, the side view is 157 pixels by 579 pixels and the front view is 333 pixels by 579 pixels. Use these dimensions to create a plane in Maya or the 3d software you are using.
Our images are now prepared! So lets go to step 2 to put the images into Maya.
Step 2: Display your reference images in Maya
Start by creating a plane and assign the width and height of the plane using the dimensions we have gotten earlier.
Next, open up the hypershade by going to the menu and select Windows> Rendering Editors> Hypershade. Create a new blinn material and name it as ironman_frontview.
Click on the checker box beside the color attribute to add a file. Select the option and locate the ironman_frontview.jpg image we have prepared earlier on.
Assign this material to the plane by first selecting the plane, then move your mouse over the material and hold down right click drag up to assign material to selections.
Once you have done it, press the key 6 in your viewport to make sure we are able to see the texture on the plane.
If the image is not in correct proportion, click on the plane and switch the dimension of the height and length. If the image is chopped off on the plane, use the UV texture to correct its UV mapping.
Rotate this plane upright to make sure it is facing the correct direction in the view port.
Do the same steps to get the side view reference image plane ready.
We are now left with 1 more step to lock the reference planes so that we do not click on the references accidentally when we are modeling.
Step 3: Locking your reference images
Select both the planes and open up the layer editor tab.
At the bottom of the panel, we should see under Display tab. Find the right most icon that says create a new layer and assign selected objects, click on it. You had just put these 2 blueprint image planes into the layer.
Lock this layer by click on the middle box two times, until you see the letter R appeared in the box. This means all your objects in this layer are now reference items and they will be locked and will not be rendered.
We are done with our preparation work and we can start to model by tracing!
Step 4: Start tracing your model
Start tracing out your ironman using the plane tool using the side and front view. Note that when you are tracing, do observe the shape and design your topology of your character of the object appropriately.
With reference images in place, you should be able to model faster, model with less errors because of the reference images guiding you!