Using Rotoscopes

I suppose you can go into a Zen-like state, just " be the hardware" and model a hammer from scratch. But for me, there's no substitute for modelling from reference pictures to get the correct proportions. The most powerful tools for accurately modelling real things in A:M are rotoscopes and markers.

The first step is to get pictures, photos or scale drawings, of the things you want to build. If possible get three views, same size, top, side and front. If you're interested in modelling a vehicle of some type, you might find a styrene model at a hobby store. You don't have to assemble it. Having the individual parts allows you to look at them from all angles. You can also take photos of the parts to use as rotoscopes. Photograph the reference objects with a zoom lens set for maximum focal length (maximum magnification). Increasing the distance from the camera to the object minimizes the perspective distortion in the roto. The same holds true if you're taking digital pictures of scale drawings.


Try to have your rotoscopes contain readable dimensional references, at least overall length, width and height. The two images above are rotoscopes I used to model a railroad flat car. The beauty of building railroad stuff is the existing model railroading "infrastructure" is pretty fanatical about scale, so most reference drawings have dimensions. If you're starting with photos or drawings, you can draw dimensions (sampled from the real thing or make an educated guess) directly on the picture.

If you use a camera, put a reference length in the picture along with the subject. I use a wooden yardstick. Even if I can't read the dimensions directly, I still know it's 3 ft. long. Or if you don't want to look like a dork taking pictures of yardsticks, bring along a photogenic friend whose dimensions you know well.

Take your reference pictures and if they aren't already, scan them to a digital format. If your scanning, don't overdo the resolution. The larger the image the longer it takes to load and manipulate. I find 960 x 720 to be a good trade-off between resolution and ease of use.

To make the images more roto friendly open them in a paint program. Reduce the saturation to limit the pallette, if necessary increase the contrast to make the shapes more distinct and paint out the background so the object is floating on a single colour background that will contrast clearly with your chosen cp and spline colours. All this image manipulation will make it easier to see your model on top of the rotoscope.


In the PWS, right click on Images and Import Image/ Animation. Import your pictures. Select each image's name in the list brings up the Properties window where you can select a colour to be blank (Key Color) when the image is displayed.

When it comes to questions of scale I like to model full size from the start. So turn on Markers and lay some in to indicate the dimensions that you put on your rotoscopes. In the case of the flatcar, I picked the side view and put markers to show the ground line at 0 in. and at +/- 240 in. for the 40 ft. length.



Right click on the model name in the PWS and then New, Rotoscope. Selecting an image brings it up as a roto in the Decal group. Clicking on the image name brings up the Rotoscope Properties window where you can select the view in which it appears as well as toggling its visibility and its pickability.

Go to the desired view. After the roto appears, align the dimensions in the roto to match the markers. Put the cursor in the image's centre to move it and grab one of its corners (while holding the shift key to maintain the image's aspect ratio) to scale it to the correct size. Run this same play with any other views. Once your roto's are full size, the model you assemble over it will be too. Once you have the rotoscope optimally positioned, always un-check Pickable so you don't accidentally move it. Now your ready to start splining, confident that everything you create will be full scale.

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