Here’s a cool lens upgrade that increases the FOV of the VFX1 from 35.5 degrees horizontal to about 50 degrees horizontal. The change is quite significant. It will however lower the resolution slightly as the few pixels the VFX1 does have are spread even further out.
I used a lens called the TS WA 17 from Teleskop-Express. You’ll need to remove the lens barrel and even cut off the barrel threads. Once that is done the LCDs of the VFX1 and be brought into focus by setting the depth of the lens in the original housings and then securing them in place using the allen set screws on top and bottom. The image below shows a lens with the threads cut off on the left and the lens with the barrel threads still in tact on the right.
You can see the difference in FOV achieved looking at the images below. There are some aliasing artifacts in the images but they’re not present in the eyepieces when looking at them. The image resolutions are 4608×3456, so if you view them full screen the aliasing will go away. Both images are the same resolution and taken with the same camera with the camera set where your eye would be so they can be directly compared. The eyepiece on the left is the stock plastic lens at 35.5 degrees horizontal. The eyepiece on the right is made of glass and is approximately 50 degrees horizontal.
The pin cushion distortion isn’t quite so bad when actually looking at it. The scene in the images above are from Skyrim.