In a word no. You are likely to include everything you can see. The problem with suprer wides, and accessory finders, is getting the camera orientation correct. I use super wides for architectural shots, cropping the lower half foreground to have corrected verticals. But the horizontals also matter. For this reason my favourite film camera for a 21 or 18 is the M5. It is a large flat body. It is necessary to have the film plane parallel to the face of the building minding not just the vertical orientation but also the horizontal, or the building will shrink towards the sky or the ground, or to left or right. Finally before pressing the shutter button I leave the accessory finder (18 is as wide as I have) and I use the camera's VF and particularly the rangefinder patch to level the camera.