When we first begin a project, it’s sometimes difficult to get our sizes correct and our shapes resembling the real world. It’s tough just to jump in and model something when we are looking at a boring default cube and wondering where to start. We need some sort of reference to work from. We often begin a virginal drawing by creating a set of rough shapes. This is called Block Modelling, and there is a whole article on that here. However, before we start block modelling, we have to know how large and what shape to make our blocks. That’s where our reference drawing comes in. We need a guide as to how the object is supposed to look. This may be an orthogonal blueprint, or it might be a photograph or even just an artist’s impression. We have to start with something, and we have to get it into Blender, where it is readily available to confirm the accuracy of our model but can be made invisible when it gets in the way.
I would like to deal with this concept of having an image to use as a cross-check by using a concrete example. Elsewhere on this site, there is a series of articles on building a vintage Bentley sports car model. To start building such a model, we first need a reference.
Here is an image of a reference which I found online:
Change to the required ortho view by pressing , or
Change to Object mode
Now simply drag the image into the blender:
The image comes in as an Empty, which contains the image. (An Empty is just a holder. It has no size, shape or colour, but it does have an origin point. In the case of a dragged-in image, think of it as being a transparent envelope. Empties usually have objects as children and are used to move and rotate those children around.) In this case, the Empty has one child – the image itself.
A reference image often needs to be semi-transparent so that you can see stuff behind it. You can adjust the amount of transparency by clicking the Object Data Properties tab in the Properties editor panel and dragging inside the Opacity slider-box:
If you want to see the reference image in Perspective view as well as Ortho view click the appropriate checkboxes.
Another method to bring in an image is more cumbersome but offers more options. It is usually used when an image is brought into a drawing as an image (a picture or decal), not so much as a reference. To get that image into Blender, we first enable the addon “Import Images as Planes”. This addon comes with Blender, but it is not activated by default.
Then scroll down to Import-Export: Import images as planes and tick the checkbox.
Click the down-arrow and the following entry will appear:
How do we use this “Import Images as Planes” Addon?
When the addon is activated, you access it by clicking the File pull-down menu and selecting Import :
The Blender File View window appears, and you can navigate to your image file somewhere on your hard drive. Select the required file and click the button Import Images as Planes. Leave the default settings as shown:
The image is brought into Blender as an object which acts exactly like a plane. The object is given the bitmap image as a material. In this case, the image filename is BentleyOrtho.jpg, so the object gets the name of BentleyOrtho automatically assigned to it:
But… That’s all very well, but I don’t see any image? Look at the picture above, and you will see from the red ring that we are currently in solid mode. Change the Viewport Shading mode to Material Preview :
Now you can manipulate this plane any way you like. Most often, the plane will lie in an orthogonal orientation. If you need to change its orientation, go into the appropriate “end on” orthogonal view and rotate our plane 90 degrees. (Make sure the Cursor is in the middle of the plane) :
Once you have rotated it, go to perspective view to check the orientation.
There are many more options available in the add-on. Experiment with them and see what they do.
Typically, you will want to scale this plane to your required size. As long as you know one real-world dimension between two points on the image, you can scale the whole image, and it will then display the correct size of the real object. See this article.