If you don't know what orthographic projection is vs. perspective projection, I would suggest googling it[www.google.com] because I think others could explain it better than me.

Essentially, everything you see with your eyes in the 'real world' is perspective projection, where parallel edges converge off into the distance. Isometric projection, on the other hand, is an artistic technique that keeps those edges parallel and doesn't let them converge. Viewing an object like this in the 'real world' is not possible so it gives the image a stylized, schematic-like look.

Link: Example Ship Used

Use Google Image search for "isometric art" for some good examples[www.google.com], many phone games use this art style. Isometric projection is a type of orthographic projection. Not to be confused with "low poly" art style which many games use at the same time as isometric projection.

The goal is to get as far away from your vehicle as possible, so increasing your view distance in the graphics settings will help.

From the game's menu go to: Options -> Video
and set:

• Deco Distance -> to as far as possible
  
• LOD Quality -> to as high as possible

Other settings may make things look better such as:

• Texture Resolution -> to as high as possible
  
• Shadow Quality -> to as high as possible
  
• Antialiasing -> to as high as possible
  
• Depth of Field -> to off (for a clearer screenshot)

You may need to restart the game for some of these settings to take effect.

• In a Creative world, spawn your ship wherever you'd like to get the lighting and background conditions you want.

• Spawn a "Heavy Sniper Rifle (Epic)" by pressing the item menu key ('H' by default).
(If you wish to do this in a non-creative world, check the end of this guide)

• Move as far away from the ship as possible without it disappearing.
(The farther you get, the closer to perfect orthographic projection your screenshot will be)

• Press the 'HUD Display Mode' button about two times to hide the heads-up display ('F6' by default).

• Look down the sniper rifle's sights and zoom in on your ship ('Right Mouse Button' and 'Mouse Scroll Wheel' by default).
(If your heads-up display is disabled correctly, there shouldn't be any black reticle)

• Center your ship on your screen and press the screenshot button to take a screenshot ('F12' by default for Steam Screenshots or 'F7' for In-Game Screenshots).

• Done!

Play around. You'll probably notice that some lighting and saturation conditions change when looking down the sight.

If you wish to do this in a non-creative world, you can do so with console commands and admin rights.
To spawn the rifle, you can enable the item menu by:

• press the tilde key (~)
  
• type "itemmenu" without the quotes
  
• press enter
  
• now you can bring up the item menu with its button ('H' by default)

You can also type "gm" to fly around and clip through objects.
(This makes positioning yourself much easier)
With flying around, hold 'Shift' and 'Ctrl' to move around very quickly.

To take high quality Steam Screenshots:
In Steam, go to:
Steam -> Settings -> In-Game
and press the 'Screenshot Folder' button
then select a folder you wish for screenshots to be saved in.
Also enable the option 'Save an uncompressed copy'.

This will export a high quality PNG screenshot to that folder whenever you take a Steam screenshot in any Steam game (button is 'F12' by default).

You can crop-out the background of your new ship screenshot with a photo editing program such as Adobe Photoshop or GIMP (which is free).

I would recommend placing your ship over a clear sky or water to make the background more uniform and easier to remove.
There are many tutorials on YouTube about removing backgrounds with photo editing programs.

Also, as mentioned by Phoenix in the comments below, you can make a green screen with steel and green coloring.

Use large steel blocks (CV or BA) to build a wall and color it with the texture gun using the smoothest texture and green or blue coloring. This gives the image a very uniform background, making it very easy to remove.

This technique is referred to as chroma key[en.wikipedia.org].

This guide tries to get as close to true orthographic projection as possible but it will still have some perspective distortion since true orthographic projection is impossible with this technique.

If you're taking a photo of a very large object, I would suggest taking multiple photos and stitching them together in a photo editing program to reduce the distortion.

Hope You Enjoy!
Made by Fieldstone, Steam ID: 76561198094512025