How effective is R6's IBIS with EF Lenses?

bodeswell wrote:

ArtHeals wrote:

I use a couple of Canon EF portrait lenses (135/2L & 85/1.8 USM) with EOS R and I don't have any major problems as i keep the shutter speed around 1/200 most of the time. But I was wondering how effective is the IBIS on R6 with these EF lenses. Is it still 5-axis with EF lenses or downgrades to 3-axis?

Some used R6's are popping up here and there and I am contemplating if its going to benefit my STILL images in any way - (No interest in video)?

Thanks in advance

I have an R5 and a 135/2L. It works great with the IBIS on. In fact, I haven't noticed any problems with IBIS using any EF lens.

What are your expectations?

My comments are based on the fact that with the same shutter speed, I seem to get a higher percentage of pixel-stable images with my 90D than with my R5, with the same EF IS lens, when calmly shooting a static, detailed object, despite the 90D's smaller pixels causing more magnification at 100% pixel view.  If I had not achieved that level of stability with the 90D, I might not think that anything is wrong, but added IBIS (X/Y and roll) seems to be subtracting stability, not adding any, in about half of images.

Now, what IBIS promises is to meet "CIPA" standards, which are very, very lax at the pixel level, corresponding to the stability seen in a postcard viewed at 450mm.  So, unfortunately, IBIS can actually cause a loss of microstability while still achieving the CIPA standard.