A firend of mine has sent me a few raw files taken with a canon 100-400 is lens.

The images look ok at 100 end, but not too good at the 400 end

Below are the links to the raw images.

Any advice would be excellent

Thanks

One

Can't see the images.
Are the pictures soft at the 400mm end?
Some have reported softness with the 100-400mm lens at the 400mm end, especially with the older models.

Hard to say for sure without seeing the images but it may need calibrating or simply exchanged for another lens (depending on how it was purchased).

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A firend of mine has sent me a few raw files taken with a canon 100-400 is lens.

The images look ok at 100 end, but not too good at the 400 end

Below are photos taken through the range

Any advice would be excellent

Thanks

They all look like junk, to be quite frank.  My 100-400 is sharper with a 1.4x and 2x TC combined for 1120mm than your 100mm shot is.

It looks to me like your friend doesn't know anything about taking stable pictures.  They all look like the lens and camera are oscillating on a tripod.