Autofocus Tokina 10-17, Sony A6500

Hi all,

I'm using the Tokina 10-17 with a Metabones adapter (mark V, latest firmware) on an Sony A6500 (Zen 100mm domeport if that is of any relevance). I do like it very much except for the autofocus. I tried AF-C, that didn't work out at all for me, so now I'm using AF-S.

I still find the autofocus quite slow, and in low light it really has trouble locking on the target. If the conditions are good and it locks, the shutterlag is still quite long. This would be a major drawback for large pelagics.

I was thinking about using back button focus in conjunction with DMF. This way I can focus (or prefocus) and I still have the MF support in terms of red highlights on whatever is in focus. The I could shoot it a bit like the best of both worlds hopefully: no shutterlag as with MF, autofocus like AF-S, and if all else fails, I just prefocus on something in the right distance and use it like MF.

Any thoughts on this?

Thanks!

The jump in AF performance from the a6500 to a6400/a6100 was pretty big. 

I shoot an A6100 in an A6400 housing, with the Zen dome, but with the Sigma MC-11 instead, and have none of these issues. The AF performance is instant and like a native lens when UW. 

Well, then I'll have to wait for the Sony A6700... what a shame, a reason to buy more stuff

10 hours ago, CupOfCoffee said:

Hi all,

I'm using the Tokina 10-17 with a Metabones adapter (mark V, latest firmware) on an Sony A6500 (Zen 100mm domeport if that is of any relevance). I do like it very much except for the autofocus. I tried AF-C, that didn't work out at all for me, so now I'm using AF-S.

I still find the autofocus quite slow, and in low light it really has trouble locking on the target. If the conditions are good and it locks, the shutterlag is still quite long. This would be a major drawback for large pelagics.

I was thinking about using back button focus in conjunction with DMF. This way I can focus (or prefocus) and I still have the MF support in terms of red highlights on whatever is in focus. The I could shoot it a bit like the best of both worlds hopefully: no shutterlag as with MF, autofocus like AF-S, and if all else fails, I just prefocus on something in the right distance and use it like MF.

Any thoughts on this?

Thanks!

Hi CupOfCoffe,

I cannot comment on Tokina 10-17/Metabones MV/Sony A6500. I did, however, use the Canon 8-15 (and Tokina 10-17) with Metabones 1x and 0.71x adapter on Olympus EM1II. AF (also C-AF&tracking) worked very good with both lenses. Now I have Sony A7R5/ Metabones MV/Canon 8-15 and C-AF&tracking works, but sometimes there are troubles. Clearly less well as with EM1II and the Metabones EF/MFT adapters, but I would rate it o.k., but by far not perfect. I think it  is a problem of Canon-EF to Sony E mount adapters...

There are also two modes with MetabonesV adapter: a LED is glowing in red or blue, depending on mode. In my case the LED glows red. Maybe the blue mode would work better (I find the complication with two modes just annoying, switching between modes seems labourious, I do not understand why Metabones makes it so complicated)...

Wolfgang

Hi Lewis,

I use the Tokina/metabones combo with an 6500 and have come to the same conclusion as you, I shoot the lens in DMF mode primarily for CFWA and pre plan my expected shooting distance for larger pelagics. Pre planning my pictures in this way has had the secondary effect of the quality of my images increasing as well, with the drawback of taking a little longer to recalibrate when another opportunity arises. 

Hi all,

Thank you for your input, I appreciate it!

I'll try the different modes (googled what I need to do...what the flying f***? Why?), and we'll, if that doesn't help im going to stick with DMF and practice...

Sharkhottub, why does it take longer to recalibrate? I was only trying on land and have trouble seeing the issue, but keen to learn!

Best,

Fabian

13 hours ago, CupOfCoffee said:

Well, then I'll have to wait for the Sony A6700... what a shame, a reason to buy more stuff

It is probably worth trying a few different things, for example changing adapter mode to see if the AF speeds up.  It may also improve with the 8-15 lens?  Is the lens slow to focus on land as well?  if so testing a few things on land may be helpful and less troublesome than trying it in water.  I believe some lenses work better if you supply USB power to the adapter through the port.

Looking at the metabones page they list the Tokina 10-17 as compatable and says they have tested with the A6500.  It specifically says this is the case for Phase detect AF - not sure how you would ensure that on the 6500, but worth checking.  The following notes are included:

• Autofocus may have difficulty locking onto subjects which are very close to the nearest focusing distance of the lens.
• Autofocus accuracy depends heavily on the design and working condition of the lens. Lenses with hidden problems which may not be apparent on Canon DSLRs will lead to inaccurate and unreliable autofocus on Sony. Typical problems of this kind that we have seen include an unsmooth/erratic autofocus mechanism (e.g. getting stuck intermittently at a certain focusing distance), a faulty/worn-out distance encoder or other faulty/worn-out internal sensors.

It might be worth trying other lenses or other samples of the Tokina.  It might also be worth contacting Metabones for advice, they can be responsive. 

On 7/6/2023 at 3:46 PM, Lewis88 said:

The jump in AF performance from the a6500 to a6400/a6100 was pretty big. 

I shoot an A6100 in an A6400 housing, with the Zen dome, but with the Sigma MC-11 instead, and have none of these issues. The AF performance is instant and like a native lens when UW. 

I shoot on the 6500 with the sigma and don't really have the issue either, video hunts a bit on the other hand. I believe Metabones is the overlying issue as I know many other people who find the same issue on photo mode with the metabones but not with the sigma