I'm not 100% sure, but I think they used a inkjet to produce those prints. They certainly do up to 80x60cm...
And no, April, I was much more adventurous... I ordered a few test prints at various print shops and picked the one that I liked best in terms of color accuracy, media quality and service. Then I ordered a print in a smaller size and checked that it works ok. Then I simply went for the big size. The price was rather moderate.
The main problem is to handle those huge shots... framing is inacceptably expensive, especially if you want really good glass. So I chose to glue them onto a polystyrol plate. In fact, I let that do someone who does that professionally. But even then, the difference in the dilation/expansion coefficient of the paper and the polystyrol made them bend inapproprately when hanged in the sunlight. So I also had to glue a thin wooden cross to the rear of the plate.
All in all, the print certainly isn't really very high quality. I also had to few pixels to produce a fineart print in this size. But when looked at from a good distance, the print really worked very nicely. See the attached snapshot.

cheers
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