Sigma 15mm fisheye + MC-11 on Sony A7RIV

[Davide DB 425]

I copy and paste my previous message in a proper thread that could be very useful for future users.

I'm helping my buddy with a Sony A7RIV + Sigma 15mm-MC-11 combo.

The camera become completely unstable.
It switches itself between AFS and AFC. Occasionally it focuses or the screen goes black.
The aperture does not work.

We initially tried with original fw and then updated camera and ring to the latest fw version
The sigma manual explains that if the ring led is off, the lens is not compatible and Sigma does not list the 15mm as a compatible lens but I trusted the many users here in the forum.

Given the so many references here for this lens, any suggestion?

At this point we will try the Metabones smart adapter V asap.

Is there some reason not to chose the Meta Smart Adapter IV over the V? 

Thank you all

[Isaac Szabo 90]

I think you're on the right track with the Metabones adapter. I don't recall any issues when I briefly tested it with the Sigma 15mm a year or two ago. I haven't tried the MC-11, but a google search reveals a number of reports of it not working properly with the Sigma 15mm.

Alternately, you could keep the MC-11 and get the Canon 8-15mm instead. That should give better image quality than the Sigma, though I don't know if it's compatible with the same dome/port you're using. 

Edited December 6, 2022 by Isaac Szabo

[Davide DB 425]

I'll let you know.

Probably latest camera/ring fw update broken the lens compatibility.

He will change the adapter first. Now our priority is having a working camera 

Then we will check for image quality. We have several extension rings and a underwave/igloo cristal dome so we could swap to Canon 8-15mm if quality is not adequate.

[waterpixel 66]

5 minutes ago, Davide DB said:

Probably latest camera/ring fw update broken the lens compatibility.

It must be that, probably on the camera side as it works flawlessly on A7III (i have had no issues). Shame as the MC-11 is a pretty cheap adaptor compared to Metabones! Your friend can find some pretty good deals on ebay (i had gotten one there I recall)

[Davide DB 425]

Yes we are scanning the net

Metabones Smart Adapter is expensive.

it's a shame for the MC-11. We thought that having lens and adapter of the same company was the best choice...

[Isaac Szabo 90]

You may also look into if there are any other settings you can try changing. I don't have any experience with the MC-11, but with my Metabones IV there are two modes available for the adapter. If I remember correctly, one emulates a Sony adapter and works well with the camera's I've used (A7R II, A6300, A6500). The other emulates a native Sony lens and doesn't work as well with my cameras. Additionally, my cameras have an "AF system" setting that must be set to "Phase Detection AF" and not "Contrast AF" for the adapter to work well.

As for the price, here in the US the Metabones IV can be bought used for around $100, which doesn't seem bad to me. But I don't know if you're open to buying used or if the used market is different for you in Italy.

Edited December 7, 2022 by Isaac Szabo

[Davide DB 425]

I can confirm that Sigma 15mm with Metabones Smart Adpater IV on a A7RIV works as expected.

it means that the latest firmware upgrade on A7RIV body and Sigma MC-11 broke compatibility with the Sigma 15mm lens (it was never declared compatible by Sigma, actually).