Parhelia with fresnel lens

The Parhelia triple scenery monitor setup can be enhanced by adding a large fresnel lens for the spanned scenery. The 40" fresnel lens was just wide enough for the 3x 15" LCD panels. The final result is really nice, as the magnification and depth added by the fresnel lens makes the front view really feel "out of the window". 

The distance lens - LCD will determine the magnification factor. Compromises have to be made with respect to distortion, color aberration and ease of view. (no headache). Below drawing shows the optical magnification:

And a picture of the result:

Note: to make this picture, the 3 views were photographed separately

Comparing with the 18" cockpit view gives you a rough  idea of the magnification factor.
The actual view is quite good, only some color aberration at the sides. The field of view is pretty large, you have to turn your head to take a look left or right.

Experiments with my 93x44cm lens with 56cm focal distance have shown that for optimal results, this lens had to be about 33cm way from the LCD screens. Viewing distance from the lens should be equal or less than the focal length. I'm sitting about 55 ~ 60cm from the lens, which is already a bit far. 50cm would be better.  Larger viewing distance will result in magnifying distortion at the edges. The lens 93cm width is just a bit too short to see the full 3x15" LCD's (totally 96cm wide) in one view, but a slight turn with you head will show the edges as well. A100cm width lens would be a bit better for this view setup. 

I find the above solution the best of all my view setup experiments so far. It requires less space, is easy to setup, does not require room lights to be dimmed, no noise or room heating (like with projectors). Screen breakup over L/C/R view is quite acceptable,  and contrast , light output, and surround view feeling is better than with projector setup, probably because the room in front of you is blocked by the fresnel lens.  

The frame on which the three LCD monitors and the Fresnel were mounted was build with adjustment flexibility in mind: The shelf-rack metal is very handy for this kind of construction. The whole display is mounted under a slight angle, as I'm looking up to the screen. The outside scenery sits a little too high as the big 40" Fresnel aspect ratio does not really fit the three LCD panels in height. I could cut off part of the top and bottom of the Fresnel, but I didn't have the courage to do so yet.
The fresnel sits in isolation foam tubing. Fresnel lenses are very easy to scratch.

It is also possible to use three smaller lenses placed next to each other. See here for more info. 

Finding shops that sell large Fresnel lenses is not easy. Sometimes they are used as screen magnifiers for TV sets. Someone recommended this shop. also sells Fresnel lenses, and the F550 type seems most used with LCD's. Update: no longer sells the F550 type lenses. I have been told that TV magnifier lenses also can be used.
Google ebay for these type of productsThis factory in China also sells lenses, up to 100x100cm, but I did not have any contact with them.

Update: To fit the screens to the DIY Motion Platform II, I build a lightweight wooden structure to mount the whole thing fixed to the simpit.

The final setup should have the area from lens to LCD's enclosed in a black coated box, see full enclosure pictures below.

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