I have a 16x20 project from scratch in the making, and so far the camera is finished and lens is on its way (A 24" Red Dot Artar in shutter) but I still lack a back and a film holder (considering the price of film and my tendency to expose what I carry I want to start with just one holder).
Maybe I will try to build a holder but buying one is also an option.
Does anyone one know of where to buy 16x20" holders?
Here's an option for what is probably the highest quality available. They're expensive, but really excellent. I've been adding whole plate format holders as I can afford them.
Lotus will make them in any size you want - I talked to them about getting some 12x15 holders made last year. Don't forget in the US, Richard Ritter (lrg4mat.net), S&S, and Alan Brubaker. The guy who makes Argentum cameras in ¿Czech Republic?/¿Hungary? might also make custom holders for less than Chamonix holders. I think he was selling some 11x14 holders on Ebay not long ago.