You will need a Hopper 3 or Joey 4K to watch in 4K. Dish showed the 2016 Rio Olympics in 4K on their rebroadcast channel. But again, you need a Hopper 3. It seems there may be 4K plans for the 2018 Winter games also. https://communities.dish.com/t5/At-Home/Winter-Olympics-in-4K/m-p/5
I am prefacing this comment with with a caveat that I am not a techie and don’t claim to be.
After reading comments about the error message 1540 on 147-05 and 540 purporting to show the Olympics in 4K, I began thinking about my hook up for my Sony 65” HD 4K HDR TV. My Hopper3 is connected via an HDMI cable to a Sony Soundbar system, which then connects to the Sony TV through another HDMI cable into HDMI 1. So I decided to conduct an experiment. I bypassed the Sony Soundbar system and ran a different HDMI cable from the Hopper3 to HDMI2. I turned on the TV and Hopper3 and tuned to 147-05. Voila, a crystal clear picture, although the sound had to come through the TV speakers instead of the Sony Soundbar. I got the same result in channel 540. The TV display shows the picture is being received 3840 x 2160p 4K. The picture is awesome. The error message I was receiving about an unsupported TV no longer displayed. In my case, the Soundbar was acting like a speed bump that didn’t allow a 4K connection. I would think Tech Support should think about this, ask questions and offer this as a solution.
I am assuming that the HDR issue remains for sets not HDR compatible, but simply bypassing the Soundbar solved my problem. Just tossing this out as a fix that worked for me.