Matching a 3D Model to the Photos (1)

This summer I was asked by some readers for making a tutorial on my photo-matching method. This method allowed me to recreate the shapes of  various historical aircraft with greater precision than the classic scale plans. (For example – the Fokker D.V or SBD Dauntless). This is the first post on this subject (I decided to split this tutorial into two subsequent posts).

Here is a printable (PDF) version of this tutorial. It contains much better images than the automatically processed copies, which you can see in this post.

The goal of the photo matching is to set up in your 3D environment a photo as the precise reference image (a more reliable equivalent to the scale plans). You can then use such a photo to verify, correct, and enhance the initial version of your 3D model. To begin, you need:

  1. Initial 3D model. First you have to prepare an initial 3D model of the aircraft. You can do it in the classic way, using available scale plans and photos. This first approximation of the real aircraft does not have to be too detailed – prepare just the fuselage, wings and empennage. Eventually you can also add simplified landing gear (placing plain cylinders in place of its oleo struts) and the propeller blades;
  2. High-resolution photo. Ideal reference photo should be detailed and free of barrel or pincushion distortions (i.e. it should depict the aircraft in a pure perspective projection). Of course, in practice such an ideal is not possible, but I will give you some hints how to identify a good candidate for the reference photo;

I built my models and matched them to the photos in Blender 3D program. In this post I am using Blender 2.80 (this is the actual version). I assume that the Reader knows the basics of Blender environment, in particular its UI and the navigation in 3D scene (“3D View” window). However, sometimes in this post I will describe some details of Blender commands that are obvious to its regular users. In this way I just want to minimize the risk that eventual Reader will “get stuck” in the middle of the described process.

For this tutorial I decided to use my old P-40 model, shown below. I built it several years ago in a “classic” way: using the scale plans.

In this old model I did not used any information from the P-40 blueprints, which I presented in my previous posts.

0103-01
Figure 103-1 An initial model of the P-40

Continue reading Matching a 3D Model to the Photos (1)

Recreating the Wright R-1820 “Cyclone” (3)

One of the most prominent features of the R-1820 engine cylinders are their rockers. More precisely – their covers, cast as the part of the cylinder head (Figure 85‑1):

0085-01
Figure 85-1 Cylinder valves and their rockers (a cutout)

The R-1820 was a classic four-stroke engine. Its cylinders had two valves: single intake valve, connected to the supercharger via a wide pipe, and single exhaust valve. Movements of these valves were controlled by cams, via pushrods and rocker arms mounted in the cylinder heads. The covers housing these valves and rocker mechanisms were placed on the right and left side of the cylinder head.

Continue reading Recreating the Wright R-1820 “Cyclone” (3)

Reverting Perspective Distortion and Other Tricks

In this post I will show you how do I create Dauntless side views. First I used the “semi-orthogonal” photo of the SBD-5 as the reference to draw the side view of this version (Figure 4-1). This is the most important picture, because it provides reliable “general reference”:

Figure 4-1 Side view of the SBD-5 and its most important photo reference
Figure 4-1 Side view of the SBD-5 and its most important photo reference

Continue reading Reverting Perspective Distortion and Other Tricks