Autofocus crashing with sigma lenses on Canon EOS RP!!

[roymickson]

Anyone here use an RP and experience autofocus issues with non-canon EF lenses?

I have a sigma 105mm macro 2.8 and a 100-400, both attached using a RF-EF Adapter. Occasionally the autofocus seems to stop working usually when I’ve not taken a shot for a minute or so. Sometimes I have to either switch to manual focus and then back to auto, or if that doesn’t work, power off and back on. I miss shots sometimes when this happens and it’s frustrating.

I’m not certain if it has happened with my RF 24-105 canon lens but it definitely doesn’t happen as often if so. Not sure if maybe the 3rd party lens is less reliable or buggy with the canon firmware or if perhaps it’s a camera body issue, or adapter issue.

If anyone has had a similar problem, I’d love to hear their experience especially if they’ve found a solution.

[diverhank]

I only have one Sigma lens, a 150-600mm C and so far I haven't run into a problem like this.  There are a couple things you might want to try, for what it's worth:

1. keep your Sigma lenses firmware updated to the the latest.

2. Go to the RP menu - Orange tab - C.Fn II:Autofocus, Sub menu 4 - Lens Drive When AF Impossible and make sure option 0 :continue focus search is enabled.

[johneos1]

There is a new Sigma firmware fix for this and several other problems with Canon Eos cameras.

[ebiggs1]

"... if perhaps it’s a camera body issue, or adapter issue."

Keep in mind it is not Canon's job or goal to see or to make third party lenses or any gear for that matter work with Canon cameras.  For the R or RP at this time you are probably better off sticking with Canon lenses.

Third party lens makers have to reverse engineer or guess how Canon camera AF system works. Canon does not document how their AF system itself works for other manufacturers.

If I was Canon, I wouldn't do it either!

[nodarsej1961]

I have a Sigma 50mm 1.4 and an R6.  All equipment are at the latest firmware and I have the same problem.  I know it may not be a Canon issues, but if anyone has an answer to solve the problem I would appreciate posting it here.

[ebiggs1]

The answer is to go to Sigma. Sigma will probably come out with a FW update to fix it but you will have to ask them. 

Canon can not and will not answer why Sigma lenses don't work on the R series cameras.