Apologies for what is probably a newbie question. I have an MPP 5x4 monorail with the standard bellows and a 150mm lens. I'm planning to shoot a series of photos of a large construction project in my area, over a period of time, all from the same vantage point. My calculations suggest I will need a wider lens, and a 90mm would seem to fit the bill. All of my lens boards are flat panels - no reccessed ones. The shots will be a general view of the subject, effectively straight shots at infinity focus - don't expect to need any movements. Am I likely to need a bag bellows? How about a recessed lens board? While I'm here, is anyone aware of other makes of lens board that fit the MPP?