Side By Side: Canon 6D / Sony A7II
Tonight is the first time we have had clear skies in quite awhile in Las Vegas,so I decided to go out and put the Sony A7II next to the Canon 6D for a low-light comparison. I am planning a weekend of star-gazing and astrophotography so I wanted to see how the Sony would perform. The catch is that I only have the Sony Zeiss 24/70mm lens for the A7II. Normally I would use a much faster lens to capture the stars. For the comparison, I drove to my favorite night sky location about 45 minutes North of Las Vegas. I love a particular Joshua tree and went there as I am familiar with the area and wanted to do this test without the stresses of finding a new location (I left the house at 9:30pm). I did not use any front lighting for the images below. It was very dark as the moon was not to rise until 1:30am. I used the same tripod (did not move it) and put a quick release plate on both cameras. To focus both cameras, I set each camera to Auto Focus, shined a flashlight on the Joshua tree, locked in the focus, and then set the camera or lens to Manual Focus mode for the actual exposures. I went by the “600 Rule” of star photography (not the ever-popular “500 Rule” that I should have used), and set the Exposure time to 25 seconds on both cameras in manual mode at f/4. To give more details on the setup: The Canon 6D is a Full-Frame camera body with a 20.2 megapixel sensor (5,472 x 3,648). I used the Sigma 24-105mm lens at f/4 and 24mm. The Sony A7II is also a Full-Frame camera body, but has a 24.3 megapixel sensor (6000 x 4000). I had the before mentioned Zeiss 24-70mm lens also set at f/4 and 24mm. I shot seven images with each camera, only changing ISO settings as follows: 400, 800, 1600, 3200, 6400, 12800, and 25600. All images were captured at 3200K white balance. The images were converted to a .jpg file and placed side by side for this blog. There was no additional editing done to these images. I know it is not the best composure, but I was just shooting this as a test. From looking at the results,I can see that the Sony seems a little more sensitive to low light. It appears that the images at the same ISO are a little brighter on the Sony side. The stars are a little soft and have some motion because I SHOULD have stuck with the 500 Rule for night photography and used a shutter speed of 20 seconds for the 24mm lens, but even with that said, the Sony seems to have a crisper star. I also think that the Sony has more of a visible Dynamic Range. You can see more detail in the Joshua tree. The larger points of light actually have a star-point look to them with the Sony images. At 3200 and even 6400 ISO, the Sony seems to handle noise better from what I can see. I am very impressed with the Sony from this non-scientific side by side test. Here are the images, I would love to hear what you think. Please remember to click on the image to see it at the full size.