Highest Resolution for TV?

Capybara#2 wrote:

In an older version of LR I could chose "Original Size" for export of.jpgs. In LRC 10 for export of a quick collection I have to select a specific size, but which one?

First, nothing has changed in Lightroom Classic 10 if you are using the Export dialog box. It is still possible to deselect Resize to Fit (so that it exports the original pixel dimensions), and if you want to use every available pixel on current and future TVs, you should still do it that way. Are you exporting a collection a different way?

Regarding the pixel dimensions for a TV, the most important thing you said is that you’re viewing it at 5 meters. However, you did not mention the size of the TV screen. Both are needed to determine which resolution is effective.

5 meters is considered a long distance unless it is an extremely large screen. There are web pages like TV Size to Distance Calculator and Science that show how distance affects resolution after taking into account human visual acuity. There is a graph about halfway down the page (“Optimal Viewing Distance by the Size of the Television and the Resolution”) that indicates that if you are sitting 5 meters from the TV, the screen should be at least 80 inches diagonally for a person with perfect vision to be able see all of the pixels in 1080p HD. For 4K at that distance, the screen would have to be so large that to see all of the pixels, you would be using a digital projector and wall-sized screen.

Two conclusions can be drawn with the help of that graph:

• If you are sitting 5 meters from a TV of the common size range of 35 to 80 inches diagonally, the most resolution your eye can see at that distance is approximately 720p, or 1280 x 720 pixels. The TV and the images on it may have many more pixels than that, but the human eye will not resolve them at that distance. 
• Resolution will not be the major factor affecting your enjoyment of the photos. The biggest factor will be the quality of editing, in particular how well the images are edited for color, levels, tonal distribution, and local contrast (detail enhancement). You will see those qualities at any distance.

The easiest way to handle the resolution question is to continue to export without resizing (at original size), so you won’t have to do it again in the future. And if you want to enjoy more of the detail, sit closer to the television. I actually do that for some of my favorite HD movies! (Because it fills more of your field of vision with the image, as shown in the article linked above.)

A standard HD TV is 1920 x 1080 pixels. That's all you get, regardless of screen size.

A 4K TV is 3840 x 2160 pixels.

So it's still a long way from any half-decent camera.