It was the DVD. I sat in the back row of the balcony and the resolution was almost acceptable. It was nice to see the '77 version with my kid in a theater. Big applause when the real Greedo scene ended and my son wanted to know why!
The weird part was that the theater manager introduced the film and claimed that this was the only version they were authorized to show. I was half-suspecting this was some sort of cover story to show 4K77, but I guess they are not that sophisticated.