This camera is a step up from the 4A-107. For the first time in Seagull's history of Twin Lens Reflex Cameras, the photographer doesn't have to look away from his or her subject in order to adjust the aperture or the shutter speed on the camera. On the other models, you have to turn the camera towards you and change the speeds or aperture by looking at the front taking lens. This is where the controls are. On the 4A-109 camera, there are 2 knobs; one for the shutter speed and one for the aperture, these are located so that you can turn them as you are looking through the viewfinder. There is a small window directly in front of the viewfinder that allows you to view these settings so that you can see the changes as you turn the knobs. This a major improvement which every photographer will enjoy.