Just wondering, when you download a 1080p SBS file and use TV SBS 3D mode to overlap, is that effectively the same as what BD 3D is doing?

Are the discs SBS files and the TV or player configured to auto adjust so that you never see the SBS? Or is it going through a different (better?) process?

Most 3D TVs, (not projectors) will process an SBS 3D file and show it properly. In an SBS file, the left and right eye images are compressed into a half-image for the left eye and right eyes. So for a 1920x1080 HD image, the left eye is compressed into 960x1080 pixels and so is the right it. This is decompressed into left and right 1920x1080 images on the screen.

A bluray 3D image, however, has two 1920x1080 images packed together in what is called a "frame-packed" image. Therefore the resolution is a full 1920x1080 image for each eye with no compression--yes somewhat sharper with a little more apparent detail.

The TV software does the adjust for SBS automatically, and you can sometimes further adjust the separation to increase or decrease the depth of the 3D image. But you can usually do that with bluray too. If you have the same movie or file available in either SBS or bluray, always go for the bluray if you can. However, on a regular 4K TV (not a projector), the 3D SBS image will be upscaled somewhat for the additional pixels available and appear to have more detail like the bluray.

Bob that depends on the 4K projector. Sony upscales all 1080P 2D and 3D, frame packed, SBS and T/B to 4K to fill the screen area the same as a 4K video. In addition they have a special upscale enhancement called a Reality Creation that allows the pixel to not just be quadrupled x4 but each new pixel is modified by the pixel it is bordered so that there are no two adjacent like pixels and the image is like a true 4K but because it doesn't originate that way the 4K is artificial. At least that's my understanding on how it works. Performance wise, a 1080 blu-ray 2D or 3D looks better with more detail than it did on a 1080P projector. Gradients are smoother and text is sharper.