Originally posted by DeadJohn It could be done but is a bad product idea. The complexity of synchronizing 2 lenses and sensors would be unnecessarily complex. Parallax errors would affect any scenes that had depth to them. Yes, it's theoretically possible to fix some of that with software processing, but you won't get noticeably improved results over a single camera and lens.
Why these problems are not affecting phone makers?
Parallax errors can also be a benefit. In the old days, camera makers spent extra effort to design and manufacture beam splitters on front of the lens. Nowadays such Steritar seems to ask for close to 300$ on eBay.
It isn't that long time ago when the idea of taking 4 pictures and combining them in software was said to be a bad product idea, unnecessarily complex and anyways impossible because of moving targets changing location between shots would anyways ruin the picture.
Originally posted by DeadJohn Film TLR cameras use one lens to look through and the other to capture the image, and don't provide the same lens change versatility we get from SLR, DSLR, and mirrorless.
Obvious. Just using the TLR name to give a connection of how could the thing look alike. A digital reincarnation clearly wouldn't just 1:1 copy the old concept.
Other usages could be e.g. sliding focusing - other lens takes the pic at f1.4 and the other f11 and then give a slider for defining the depth of field. Simplified light field.
Originally posted by Not a Number Right, TLR stands for "Twin Lens Reflex" camera. Reflex because it uses a mirror to the viewfinder. The mirror is fixed and the image in the viewfinder is reversed and upside down. SLR ("Single Lens Reflex") cameras have a roof prism to orient the image the proper way in the viewfinder. The mirror will move on SLRs (except in case on some Sonys). Even though the image was reversed on TLRs the idea was - what-you-see-is-what-you-get.
SLR's got mirror moving, TLR's -- in the old times -- didn't.
A TLR with a swinging mirror to give both lenses light path to their corresponding sensors. Nobody has implemented this, but it still would be a TLR.