Friday 14 December 2012

Using Forced and False Perspective in HO/OO Gauge with N Gauge Models


One of the challenges when modelling in smaller scales is giving the illusion of space. HO/OO and N gauge layouts are also often synonymous with limited availability of space. It seems that fewer and fewer people have access to the once ubiquitous spare room.

This means that there are two challenges to address:

  • smaller scale, less imposing models (locomotives, rolling stock and scenery);
  • less space to create the illusion of more.

Backscenes are often used to good effect to create the illusion that the layout is merely a part of a larger geographic area, as are techniques for enclosing the layout using scenic breaks (such as bridges) and varying the height of rails, embankments, and so forth.


Using HO/OO and N Gauge Together to Create False Perspectives


However, there is another option - to use smaller scale models, scenic items (such as low-relief models and trees) to create an illusion of perspective. So, OO and HO modelers can use N, or even Z guage items to represent things that are distant, provided that some basic guidelines are followed.

One great example of this in action is the MRC's Copenhagen Fields layout. The rolling stock is N gauge (actually finescale 2mm standard) and the surrounding models and scenery goes right down to 1:450 to give the illusion of vast scale.

While I accept that Copenhagen Fields is also a large layout (9m x 3m), the techniques can still be applied to a smaller layout that is only 36 inches deep. To do so, however, a few guidelines need to be followed.

Scale Differences Between the Gauges

The first thing to establish is what the scale differences are between gauges (for a complete run-down, check out the Gauge & Scale Guide at RailMania). For example:

- O gauge is 1/43.5 scale
- OO gauge is 1/76 scale
- HO gauge is 1/87 scale
- N gauge is 1/148 scale
- Z gauge is 1/220 scale

Therefore, the difference between an OO gauge and N gauge model, in terms of scale is roughly half. It follows that, from a given viewpoint, there is a point at which, if an N gauge model is placed behind an OO gauge one, it will appear to be more distant, and not merely smaller.

That is the point of the false perspective, also known as forced perspective - to use a 3D model in place of a flat backscene to imply depth, hopefully giving a more realistic result.

Because of the way perspective works, pieces of scenery that are trying to force the perspective need to be diagonally behind - i.e. up and back from - the foreground objects.

There are so many variables, that often trial and error is the best way to proceed.

Trial and Error

Firstly, you need to decide what you are going to use to create the false perspective:

  • low relief card models (i.e. from scalescenes.com);
  • modified card models (i.e. from Metcalfe);
  • modified plastic models;
  • small scale models (vehicles, people, etc.) placed on the layout, in front of the back scene. 

The obvious advantage of using Scalescenes models is that they can be easily modified, and if you make a mistake, re-printed! Destroying an expensive Metcalfe kit in an attempt to make it low-relief is a bigger risk, and the same goes for plastic models.

Once you have decided what models you will use to create the false perspective, it is a case of placing the various bits and pieces of scenery on the layout and observing the effect from different points.

You will find that there are places where the effect works, and places where it doesn't. If it really doesn't work from a particular angle, consider blocking the view with a scenic break, or changing the shape of the layout.

(The late Carl Arendt wrote an excellent piece on designing micro layouts, and one trick he used was forced perspective.)

Having gone through the trial and error exercise above, the modeler will now be acutely aware that not only is there a 'sweet spot' in which models can be placed for the best affect, but that this sweet spot will move around depending on the viewer's position.

Trawling through the forums on the topic, the accepted wisdom appears to be that forced perspective is fine for backscenes and supporting scenery, but needs to be used wisely.

In addition, while three to four feet is the smallest width that most people recommend, more enclosed 'micro layouts' work well because they naturally restrict the viewer's line of sight, thereby reducing the chance that the illusion is broken.

Finally, don't ever forget that it's not just about the models and backscene. Roads need to narrow into the distance, fences and walls will diminish, and if one part of the layout is out of kilter, the illusion will start to fall apart!