Image distortion R7 with EF-70 200 IS MkII Lens

[nibbo]

I've recently bought an R7 and use the 70-200 with EF-R adaptor. I'm finding my images are distorting with the football (US - soccer ball :-)) - In a burst it can be 1 in 3 so it does get it right most of the time, but I cant use the images for publication. Along with the problem of not being able to use wifi with my google Pixel 7 (a security issue with Google Pixels fault I'm led to understand) I'm regretting buying the mirrorless camera. I've looked up lens aberration, would it make any difference if I got the EOS-R version of the 70-200m lens. I've never had this problem with my 7D mkIIs.  

[Waddizzle]

Are you using the electronic shutter for the highest possible frame rates?

It looks like it.  This is called rolling shutter.  It is not a defect.  It is the laws of physics on display.  If you think this is bad, then you need to see what it looks like in Nikon and Sony bodies in this price range.  

If you would use the mechanical shutter or electronic first curtain, then the problem would go away.  Unfortunately, this probably means that you will not be able to use the maximum frame rates, which already far exceed the competition in this range.

[Waddizzle]

Here is a YouTube video that explains global and rolling shutters.  The only difference between capture in video and stills are your typcial shutter speeds.

A mechanical shutter exposes all the pixels at the same time and for the same length of time.  A global shutter also exposes all the pixels to light at the same time.  A rolling shutter does not expose all the pixels at the same time.

[Tronhard · Accepted solution]

As my highly respected associate Widdizzle noted, this effect is called rolling shutter.  It is caused by a design characteristic of the camera.

In high-speed full electronic mode, the shutter is repeating at a rate of 30fps. However the sensor has a large pixel count of 32MP but a high pixel density that would be the equivalent of a 83MP sensor - something no camera maker has achieved.

In electronic shutter mode, there is no mechanical apparatus in operation, instead the sensor is refreshed one row at a time, and because the sensor is not BSI/stacked (like the R3, which also has a much smaller pixel count of 23MP) the rate is too slow to keep up with moving objects, thus as the ball moves across the field of view it is distorted by the delay as each layer is refreshed and records a slightly different moment in time.

The only way to alleviate this it to slow down the frame rate to something more modest, such as 11fps.  You could employ the mechanical shutter but it is very noisy and can suffer from a bouncing effect called shutter shock.  So, first curtain electronic is likely the best compromise to work with.

[nibbo]

Thanks guys for the detailed response. It's a new area for me so I'll investigate and try to understand it! Someone did say use electronic first curtain but they said they didn't know why 😃