Try adding IR illuminators on the area you want to watch. My SD4A is useless at night. It's either too dark or after adjusting settings so I can see, I get motion blur and the image is unusable if there's any motion. I added another camera in the area where I have the SD4A. The new camera is another PTZ with laser IR. I can point my SD4A at something 250+ feet away and not see it with just the SD4A IR on max, but if I illuminate the area with the laser IR (advertised as good for 500M, and that's accurate from what I've seen - it's amazing) from the other camera, the image on the SD4A is perfect. Bright, detailed, no motion blur. It's like an entirely different camera.
So I don't think the camera is the limiting factor, though it is technically limited by the less than ideal sensor size for the resolution. The IR just sucks and it sounds like the IR on the tinted one sucks even worse. Light the area up with IR illuminators if you can and see how it looks.
