Using ef300 f2.8 on R5

[czwotzit]

I thought i'd try and see how my EF300 f2.8 lens performed when attached using the adapter on my R5 (normally I use the lens on my 1DX3). The result was that the lens started to hunt for focus in rapid stuttering steps eventually achieving focus. I found it easier to switch the lens to manual focus to get close then switch it back on. The reason I was trying it out is that i'm considering reducing my kit and have just the R5 but the 300 f2.8 is a brilliant lens and don't want to lose it.

Any suggestions on the cause or solutions

Andre

[@imagesBV]

Are you using a filter on the lens….?

[czwotzit]

No filters are being used

[SpringfieldPhoto]

Is the adapter a genuine Canon adapter? A friend had a similar problem when using a non Canon adapter.

[czwotzit]

Thanks for asking. Yes the adapter is the Canon adapter. The camera has the latest firmware but I don't know if the adapter needs/or has firmware and I haven't checked the 300 lens to see if there's an update yet.

Andre