I Added Custom Lenses to the 2016 Black Gear VR.

But ... then I put the originals back again. I'm only posting this as 'proof of concept,' to let people know it can be done.

The new lenses that I added worked, but they weren't perfect in terms of distortion and more importantly, they didn't offer better image quality than the default lenses. If I had more lenses to experiment with, I might have found some I liked better.

The default lenses are not perfectly round as everyone knows--there is a section of the circle that has been cut away to leave more room for your nose--but I didn't find this to be an issue. In other words, you can substitute perfectly round lenses for the originals if you want.

Because we can't modify the Gear VR's custom distortion, it is hard to get a perfect match with the new lenses--but the distortion with new lenses was not as bad as I thought it might be.

In addition to trying new lenses, I also removed the original lenses from their black plastic rings, and experimented with putting them on top of the rings, similar to a mod 4amusername did here:

https://www.reddit.com/r/GearVR/comments/4dqgg7/how_to_increase_fov_mod/

This does slightly increase the FOV, by bringing the lenses closer to your eyes, but more importantly, the resulting image, at least in my case, was CRYSTAL CLEAR. Very, very sharp, with a large focal point. This was the single biggest difference I saw.

Unfortunately, it is hard to re-mount the lenses on top of their holders to make sure they are perfectly aligned/balanced with each other, and so in addition to the greatly increased clarity, I paradoxically saw a slight lessening of the 3D depth. I had to go back and forth to compare a lot to even confirm this, but it was there.

I also found the lenses to be a little too close to my eyes, so that my eyelashes were brushing against them slightly. If I had a deeper face pad, I think this issue would go away.

Before all of this I had switched to an extra thin custom face pad--cut from one of those "sleeping masks" people wear--to bring my eyes closer to the image, increasing FOV and clarity ... and this remains the single best improvement I've made so far, so if you are looking for better FOV and sharpness, I highly recommend that tweak at least.

Modding or substituting the lenses themselves, is a lot more complex, and I don't really have the time right now to pursue that route, but if any of you feel like taking up the challenge ... please, keep us informed.