HELP: Aperture goes wide open when camera just turned on, but aperture read out is different (F11)

[donbros]

Before anything, I use Sony A7S III with samyang/rokiron f2.8 24 mm. I use manual or "movie" mode which is essentially also manual just for video.

So as I stated in the title, when I turn on my camera, aperture instantly goes wide open, which is not what is showed on the screen (either I have it set on f4 or f11, it goes wide open (F2.8) no matter what). It happens almost every time. It "fixes" when I adjust aperture by one stop, which is kinda annnoying, missed some shots because of that. What is the problem? Please help I am really stressed, should I go to warranty or what? And is it lens or body or something else issue? Maybe its something with settings? I was filming an awesome video and this happening almost all the time really annoyed me. Thank you!

 

[NS: Nikon Shooter]

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I don't know anything about your gear but it is normal for lenses
to open up at first so to optimise AF performance.

 

[donbros]

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I don't know anything about your gear but it is normal for lenses
to open up at first so to optimise AF performance.

But it opens up and stays till I change aperture is that normal? It would stay wide open for hours or days if I don't change aperture by one stop. I haven't seen this happen on any other lens or sony camera before.

It is especially anoying when it is super bright and aperture goes just wide open and I miss a shot

 

[NS: Nikon Shooter]

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Even on manual and a set ƒ8, it will always open fully to
close back at SR.

 

[donbros]

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Even on manual and a set ƒ8, it will always open fully to
close back at SR.

the problem is it does not automatically close back (btw I am a bit new to this abbreviation, what SR mean?). If that supposed to be like that, what is the point of it ? You said autofocus but how it would autofocus, if by going wide open and staying like that and not going to correct aperture settings on camera, it looks like this on bright day

 

[NS: Nikon Shooter]

what SR mean?)

Sorry… shutter release.

It will close to your set ƒ stop — given not defective — for a very
short but adequate period of time.

 

[donbros]

Sorry… shutter release.

It will close to your set ƒ stop — given not defective — for a very
but adequate period of time.

Thank you for abbreviation explanation.

So I tested this. I waited for 1 minutes (now 2 minutes actually) and it still not going back to my set f-stop I mean that is the main problem not going back after going wide open to set ƒ stop. if it still like that what could be the problem lens or body?

 

[NS: Nikon Shooter]

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Since I have no personal experience with your type of gear,
I'm afraid I can't help you much not having it in my hands.

 

[donbros]

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Since I have no personal experience with your type of gear,
I'm afraid I can't help you much not having it in my hands.

So all in all generally, after turning on camera, aperture/iris staying wide open (when aperture is set to something like f11) and not going back to set f-stop (f11) for extended period of time aka minutes, hours is not normal? I need to confirm this for further investigation and explanation to rma or someone else on thread. Thanks.

 

[NS: Nikon Shooter]

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When the combo is turned on, the lens always open fully and
will remain opened until triggered, only then will it close to set
ƒ stop very briefly. Again, I don't use your kind of gear, Maybe
the RFM strategy would apply to answer your doubts.

How long have you had it?

 

[TreeofLifeStairs]

It sounds like there’s something wrong. I just tested two lenses on my a7ii. On my Sony 16-35 2.8 GM lens the aperture is controlled in camera. No matter what I set it to, when I take it off (or turn it on), it goes wide open and then instantly returns to whatever I had it previously set to.

I also tried with my Sony 85 1.4 GM since it has a physical dial on the lens itself. When I take the lens off or turn the camera off it goes to approximately 5.6. When I turn it back on it goes straight to whatever I have it set to. Unlike the other lens, it doesn’t go wide open first.

I would start a ticket with the manufacturer. Is that your only lens? Do you have another to see if the problem is consistent?

 

[480sparky]

It may be a compatibility issue between the Sony body and a 3rd-party lens.

 

[donbros]

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When the combo is turned on, the lens always open fully and
will remain opened until triggered, only then will it close to set
ƒ stop very briefly. Again, I don't use your kind of gear, Maybe
the RFM strategy would apply to answer your doubts.

How long have you had it?

I have it for a few months. I had to mention I mostly do video.

It sounds like there’s something wrong. I just tested two lenses on my a7ii. On my Sony 16-35 2.8 GM lens the aperture is controlled in camera. No matter what I set it to, when I take it off (or turn it on), it goes wide open and then instantly returns to whatever I had it previously set to.

I also tried with my Sony 85 1.4 GM since it has a physical dial on the lens itself. When I take the lens off or turn the camera off it goes to approximately 5.6. When I turn it back on it goes straight to whatever I have it set to. Unlike the other lens, it doesn’t go wide open first.

I would start a ticket with the manufacturer. Is that your only lens? Do you have another to see if the problem is consistent?

Thank you for your testing! Mine is without physical dial like your GM. Yeah that is my only lens right now. I will probably start the ticket unless someone knows what could be the problem and it can be easily fixed.

It may be a compatibility issue between the Sony body and a 3rd-party lens.

What solution you would suggest? It is really hard to work with when it does that. And I doubt it is widespread issue or forum would be filled with at least a few questions like this because it is kinda very annoying when you want to shoot video fast and you have to go one stop in one direction and then go back to the one desired when camera was turned on...

 

[480sparky]

What solution you would suggest? It is really hard to work with when it does that. And I doubt it is widespread issue or forum would be filled with at least a few questions like this because it is kinda very annoying when you want to shoot video fast and you have to go one stop in one direction and then go back to the one desired when camera was turned on...

Download and install any updates you can for both the camera and lens. Maybe the bug that's causing the issue has been addressed.

 

[donbros]

Download and install any updates you can for both the camera and lens. Maybe the bug that's causing the issue has been addressed.

Just updated both still the issue persist.