We used to do murals in-house, but mostly send them out now (thank god)--but my advice would be to pay someone to do this. I could tell you how to do it by hand, --but it's a very labor intensive thing. At any rate, I work in the exhibits design & fabrication part of a museum system. We used to do them with internegs and interpos (8x10), but for the past couple of years we've been using 2 labs that do drum scans off whatever the orginal is. It could be an 8x10 print, or a 4x5 CT. the output is done on lambda or lightjet printers, on any type of plastic based photo paper that can run through a roller transport processor. So, this would be c-paper, ilfochrome etc.
5x6 is a weird size for a mural. It will probably be in two pieces on traditional photo paper. We did a 1:1 repro of a painting a few years ago, and shot it on 4x5 chrome film. It was drum scanned and output on a wide format inkjet printer onto canvas. The size was 5x9 almost. I wanted to reduce it to a 4x8 and make a cibachrome, but it *had* to be 1:1, so this was how it was done. The inks were outdoor rated, and our shop guys stretched this canvas on a frame like a painting, and gave it a UV lacquer overcoat. It hung in a public building for a few years and did a pretty good job. If you got up on it, it looked like an inkjet--but from a few feet away, it looked like a painting actually...
BTW---used to be only a couple of labs had the lightjet printers or lambdas. Now they're all over the place. There are other materials as well, like Scotchprint for one--it's used for display graphics and can be tiled together to huge sizes. Just about any exhibit/tradeshow type lab would be able to do a mural for you....we used a place down in Atlanta for years, but there's a lab less than a mile from our building now, that makes murals using a Lightjet, and does first-surface mounting etc. We've used lambda prints for signage too--you can incorporate text & images and output onto c-paper now, whereas you used to do this with silkscreen and trad. prints.
I don't think it matters which way it's done, as I've seen great murals done both ways. Using digital is a little easier though, because you don't have to get into internegs/interpositives and you're not locked into any one specific type of print material. Just whatever can run through a machine processor. The only advice I'd really have is that if you shoot color neg, get a repro grade print made and have them scan that. They want prints or transp. Talk to the lab first, and line up what they need from you. They know their setup and what they require better than you. As for what you output to, just think of how long it will be on display and in what type of conditions. The higher the traffic and visibility, and the longer on display are things to think about and may require laminate overcoats or first-surface mounting etc. We did a couple last month, that were b&w's on c-paper. One came off a pretty lousy old 4x5 (long story), the other came off a vintage 4x5 neg that was tack-sharp. I made 8x10 rc prints of each and these were used to make the drumscans. Each is a 2 piecer mounted with a lustre laminate. The cost was less than 400 each. One of the first murals we sent out years ago, cost about twice that, done traditionally and we had to mount it in-house. three pieces using spray mount---what a PIA! Send it out--the whole thing.
Hope this helps, KT
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