What went wrong with my star trail settings - A7III?

[uday029]

I recently tried to do star trails using my Sony A7iii and Tokina 20mm. This is the first time I tried star trails using my new Sony A7iii. There seems to be slight movement between each frame and I am not sure what is causing it.

Here are my settings:

• Continuous shooting mode
• Sturdy tripod
• Wired remote shutter
• Manual focus
• 30 second exposure

My initial thought was that my tripod was not steady enough but then all of my single exposure shots (30 sec) came out without any camera shake. There seems to be something causing a slight shift between frames. I have taken some milkyway single exposure shots on the same day and they were pretty sharp without any camera shake. I am not sure if I am missing something obvious or trivial. Any idea what might be causing this shift? I have attached couple of photos with star trails (zoomed and cropped) and also one zoomed in single exposure shot that shows trails without ant shift.

Thanks in advance for your time.

Star Trails 1

Star Trails 2

400% cropped single 30 sec exposure

[dewarp]

I presume that you did switch off the Steady-Shot facility? If not, that would cause such a problem.

I last took star trails with an A77. Even with SS switched off, over the space of about an hour I found that the framing jumped slightly between shots a handful of times, returning to the original position again. As a result I was unable to use automated software to combine the images and had to do it manually in Photoshop. A real pain!

regards - Peter