This image was captured with the A7II camera and the FE70200F4 lens and was captured about 15 minutes before the sun made an appearance.
Shooting with a neutral density (ND) filter is great for capturing smooth reflections in the water. The effect reinforces the tranquility of such a scene (ND200 or ND400 filters are ideal). The filter size for both the FE1650F4 and FE70200F4 lens is 72mm and so one filter will serve both lenses and you will find that you can easily capture 30 second exposures at this time of day. If you intend to captured exposures longer than 30 seconds you will need a remote release. With exposures of 30 seconds or shorter you can use the Self-timer in the Drive Mode settings.
If you shoot without an ND filter you will find you will struggle to keep the shutter speed slower than 1/30 second as the sun rises (f/16 @ 1/30 Second, ISO100). Stopping down to f/22 and lowering the ISO to 50 will lower the dynamic range of the sensor and introduce softening effects of diffraction (so is best avoided).
Top Tip: Remember to switch off SteadyShot when the camera is mounted on a tripod to ensure your images are as sharp as possible.