Back a while ago during update #36, they were discussed slightly;

 

Resolution and Scaling - We want to run the game at various resolutions and scale properly. We've been talking about our target resolutions and looking at the best way to implement scaling. If you've played any of the Infinity Engine games lately, you may have noticed that running at high resolutions can make the game look like an RTS. Though it's nice to be able to scale up and see more of the environment, at a certain point dungeons start looking like ant farms. That's what happens when you take a game designed for 640x480 and run it at more than double the resolution. It is now the year 2012, so we're looking at supporting a range of resolutions that runs from modest laptops to Macs with crazy Retina displays.

 

To do this, we're going to render the game out at a target high resolution and a target low resolution. Currently, we're looking at a base resolution of 1280x720. A large number of laptops run at this resolution or its slightly bigger brother, 1366x768. It's not quite twice the resolution of the original games (640x480) due to the 16:9 aspect ratio, but pretty close. We believe that this base resolution will scale well up to 1920x1080, which would be roughly equivalent to going from 640x480 to 1024x768. In the old IE games, this gave you a slightly larger view of the world, but didn't get too crazy.

 

For our higher resolution, we are likely going to render out to a ~2560x1440 screen size, as we did with our environment during the Kickstarter campaign.
We will likely downsample these to run at 1920x1080. With resolutions above "mere" Retina displays, we will zoom out, which should allow the backgrounds to scale into outer space (close enough, anyway).

 

Is it possible to know how it's being handled now?

Obviously there is a zoom feature, but I'm curious what the "correct" level of zoom is so that the background renders are pixel perfect, but also what the "correct size" is, as in which resolution the game was designed around scale wise.

 

Thanks!

Based on the ole' eyeball 2.0 software installed into my frontal cortex would make a cautious guess and say that the backgrounds have been designed for 1080p resolutions with 16:9 and 21:9 variants.