GFX: Is it possible to turn off aperture (compensation)?

Hi,

I am relatively new to a GFX 50S and I wonder why the apertures are constantly incrementally closing or opening while I am not touching the shutter button. Just moving with the camera in my hand, the aperture seem to adapt to the light that comes through the lens. I can't find how to deactivate it. This is particularly annoying with the Fringer adapter and with my old EF 85mm 1.2, as I fear that this might eventually shorten its life. The aperture closes incrementally to an intermediary value, and reopens when the shutter is half pressed. It does with the GF 110 too. There is probably a simple setting, but so far, I could not find it! Thanks.

It sounds like you may have the camera set for something other than Aperture Priority. If that is the case, switch to either “A” or “M” and see if that helps.

alpshiker said:

Hi,

I am relatively new to a GFX 50S and I wonder why the apertures are constantly incrementally closing or opening while I am not touching the shutter button. Just moving with the camera in my hand, the aperture seem to adapt to the light that comes through the lens. I can't find how to deactivate it. This is particularly annoying with the Fringer adapter and with my old EF 85mm 1.2, as I fear that this might eventually shorten its life. The aperture closes incrementally to an intermediary value, and reopens when the shutter is half pressed. It does with the GF 110 too. There is probably a simple setting, but so far, I could not find it! Thanks.

Click to expand...

What's the PRE-AF setting you're using?

cortex95x said:

It sounds like you may have the camera set for something other than Aperture Priority. If that is the case, switch to either “A” or “M” and see if that helps.

Click to expand...

Thanks for your answer. But do you mean, on the rotating dial ? By default it is set on A and the opening is commanded by the ring on the adapter, or by the aperture ring on the GF lens. Tried T and it is the same.

So do I have to understand that this is not normal behaviour?

JimKasson said:

alpshiker said:

Hi,

I am relatively new to a GFX 50S and I wonder why the apertures are constantly incrementally closing or opening while I am not touching the shutter button. Just moving with the camera in my hand, the aperture seem to adapt to the light that comes through the lens. I can't find how to deactivate it. This is particularly annoying with the Fringer adapter and with my old EF 85mm 1.2, as I fear that this might eventually shorten its life. The aperture closes incrementally to an intermediary value, and reopens when the shutter is half pressed. It does with the GF 110 too. There is probably a simple setting, but so far, I could not find it! Thanks.

Click to expand...

What's the PRE-AF setting you're using?

Click to expand...

Jim, it was set to OFF. If I set it to ON, the autofocus crackles in addition to the diaphragm, which makes the problem even worse.

alpshiker said:

JimKasson said:

alpshiker said:

Hi,

I am relatively new to a GFX 50S and I wonder why the apertures are constantly incrementally closing or opening while I am not touching the shutter button. Just moving with the camera in my hand, the aperture seem to adapt to the light that comes through the lens. I can't find how to deactivate it. This is particularly annoying with the Fringer adapter and with my old EF 85mm 1.2, as I fear that this might eventually shorten its life. The aperture closes incrementally to an intermediary value, and reopens when the shutter is half pressed. It does with the GF 110 too. There is probably a simple setting, but so far, I could not find it! Thanks.

Click to expand...

What's the PRE-AF setting you're using?

Click to expand...

Jim, it was set to OFF. If I set it to ON, the autofocus crackles in addition to the diaphragm, which makes the problem even worse.

Click to expand...

Well. It was a thought. Sorry it didn't work.

Just so that I know it's not normal behaviour: when the lens is directed towards a bright source of light, in mode A with a lens wide open, the aperture closes automatically to a lower aperture without any intervention. It reopens when the shutter is half pressed. ??

alpshiker said:

Hi,

I am relatively new to a GFX 50S and I wonder why the apertures are constantly incrementally closing or opening while I am not touching the shutter button. Just moving with the camera in my hand, the aperture seem to adapt to the light that comes through the lens. I can't find how to deactivate it. This is particularly annoying with the Fringer adapter and with my old EF 85mm 1.2, as I fear that this might eventually shorten its life. The aperture closes incrementally to an intermediary value, and reopens when the shutter is half pressed. It does with the GF 110 too. There is probably a simple setting, but so far, I could not find it! Thanks.

Click to expand...

This is normal behaviour for a mirrorless camera. Due to the EVF, the camera needs to provide reasonable amount of light onto the sensor to feed the EVF with the proper exposure so the user has a representation of the scene through the EVF. When you go to take the exposure, the camera will shift to the selected aperture.

If it’s really bothering you, there’s a setting in the menu to “preview depth of field” which you can assign to a button. This will stop the lens down to selected aperture and that’s what will be shown in the EVF. Please note that focus speed can be impacted if you stop down too much.

alpshiker said:

Hi,

I am relatively new to a GFX 50S and I wonder why the apertures are constantly incrementally closing or opening while I am not touching the shutter button. Just moving with the camera in my hand, the aperture seem to adapt to the light that comes through the lens. I can't find how to deactivate it. This is particularly annoying with the Fringer adapter and with my old EF 85mm 1.2, as I fear that this might eventually shorten its life. The aperture closes incrementally to an intermediary value, and reopens when the shutter is half pressed. It does with the GF 110 too. There is probably a simple setting, but so far, I could not find it! Thanks

Click to expand...

I am not entirely clear on exactly what is happening for you. But try taking the battery out for 10 seconds and then reinsert it while the camera is turned on. This seems to reset the connection between the Fringer, the lens, and the body. This cured some odd misfunctioning for me, but it didn't work if I took the battery out while the camera was turned off (which I tried first). I am using the EF 85 1.2L II with a GFX100S, so may be different from your situation.

chironNYC said:

alpshiker said:

Hi,

I am relatively new to a GFX 50S and I wonder why the apertures are constantly incrementally closing or opening while I am not touching the shutter button. Just moving with the camera in my hand, the aperture seem to adapt to the light that comes through the lens. I can't find how to deactivate it. This is particularly annoying with the Fringer adapter and with my old EF 85mm 1.2, as I fear that this might eventually shorten its life. The aperture closes incrementally to an intermediary value, and reopens when the shutter is half pressed. It does with the GF 110 too. There is probably a simple setting, but so far, I could not find it! Thanks

Click to expand...

I am not entirely clear on exactly what is happening for you. But try taking the battery out for 10 seconds and then reinsert it while the camera is turned on. This seems to reset the connection between the Fringer, the lens, and the body. This cured some odd misfunctioning for me, but it didn't work if I took the battery out while the camera was turned off (which I tried first). I am using the EF 85 1.2L II with a GFX100S, so may be different from your situation.

Click to expand...

Thanks, I just tried, to no avail. It behaves the same with the GF lenses so it's not limited to adapted lenses.

fcracer said:

alpshiker said:

Hi,

I am relatively new to a GFX 50S and I wonder why the apertures are constantly incrementally closing or opening while I am not touching the shutter button. Just moving with the camera in my hand, the aperture seem to adapt to the light that comes through the lens. I can't find how to deactivate it. This is particularly annoying with the Fringer adapter and with my old EF 85mm 1.2, as I fear that this might eventually shorten its life. The aperture closes incrementally to an intermediary value, and reopens when the shutter is half pressed. It does with the GF 110 too. There is probably a simple setting, but so far, I could not find it! Thanks.

Click to expand...

This is normal behaviour for a mirrorless camera. Due to the EVF, the camera needs to provide reasonable amount of light onto the sensor to feed the EVF with the proper exposure so the user has a representation of the scene through the EVF. When you go to take the exposure, the camera will shift to the selected aperture.

If it’s really bothering you, there’s a setting in the menu to “preview depth of field” which you can assign to a button. This will stop the lens down to selected aperture and that’s what will be shown in the EVF. Please note that focus speed can be impacted if you stop down too much.

Click to expand...

Oh, this explanation seems to answer the question. But why have other users not notice? Maybe it's because the old EF 85mm 1.2 has a particularly noisy aperture mechanism, and the fact that it is luminous exacerbates this behaviour?… I'll try your suggestion to see how it works.

Thanks!

alpshiker said:

fcracer said:

alpshiker said:

Hi,

I am relatively new to a GFX 50S and I wonder why the apertures are constantly incrementally closing or opening while I am not touching the shutter button. Just moving with the camera in my hand, the aperture seem to adapt to the light that comes through the lens. I can't find how to deactivate it. This is particularly annoying with the Fringer adapter and with my old EF 85mm 1.2, as I fear that this might eventually shorten its life. The aperture closes incrementally to an intermediary value, and reopens when the shutter is half pressed. It does with the GF 110 too. There is probably a simple setting, but so far, I could not find it! Thanks.

Click to expand...

This is normal behaviour for a mirrorless camera. Due to the EVF, the camera needs to provide reasonable amount of light onto the sensor to feed the EVF with the proper exposure so the user has a representation of the scene through the EVF. When you go to take the exposure, the camera will shift to the selected aperture.

If it’s really bothering you, there’s a setting in the menu to “preview depth of field” which you can assign to a button. This will stop the lens down to selected aperture and that’s what will be shown in the EVF. Please note that focus speed can be impacted if you stop down too much.

Click to expand...

Oh, this explanation seems to answer the question. But why have other users not notice? Maybe it's because the old EF 85mm 1.2 has a particularly noisy aperture mechanism, and the fact that it is luminous exacerbates this behaviour?… I'll try your suggestion to see how it works.

Thanks!

Click to expand...

fcracer is correct in his explanation, there is nothing wrong with your camera. This aperture behavior also occurs in my other Fuji and Sony cameras. Why other users are not knowledgeable of this is curious, it is quite easy to observe.

goodbokeh said:

goodbokeh said:

goodbokeh said:

This is normal behaviour for a mirrorless camera. Due to the EVF, the camera needs to provide reasonable amount of light onto the sensor to feed the EVF with the proper exposure so the user has a representation of the scene through the EVF. When you go to take the exposure, the camera will shift to the selected aperture.

If it’s really bothering you, there’s a setting in the menu to “preview depth of field” which you can assign to a button. This will stop the lens down to selected aperture and that’s what will be shown in the EVF. Please note that focus speed can be impacted if you stop down too much.

Click to expand...

Oh, this explanation seems to answer the question. But why have other users not notice? Maybe it's because the old EF 85mm 1.2 has a particularly noisy aperture mechanism, and the fact that it is luminous exacerbates this behaviour?… I'll try your suggestion to see how it works.

Thanks!

Click to expand...

fcracer is correct in his explanation, there is nothing wrong with your camera. This aperture behavior also occurs in my other Fuji and Sony cameras. Why other users are not knowledgeable of this is curious, it is quite easy to observe.

Click to expand...

This is actually something new to me, and really bothersome I have to say. I have the Sony A7RIV with MC-11 and the same EF 85 f1,2 in my hands, and it does not send impulses to the blades as luminosity changes, but does the luminosity adjustment electronically. Maybe this is something particular to the 50S which was changed with the 100S and 50SII ? I'm still in doubt that this works as it should, for why put such constant strain on the electro-mechanic commands?

alpshiker said:

goodbokeh said:

alpshiker said:

alpshiker said:

This is normal behaviour for a mirrorless camera. Due to the EVF, the camera needs to provide reasonable amount of light onto the sensor to feed the EVF with the proper exposure so the user has a representation of the scene through the EVF. When you go to take the exposure, the camera will shift to the selected aperture.

If it’s really bothering you, there’s a setting in the menu to “preview depth of field” which you can assign to a button. This will stop the lens down to selected aperture and that’s what will be shown in the EVF. Please note that focus speed can be impacted if you stop down too much.

Click to expand...

Oh, this explanation seems to answer the question. But why have other users not notice? Maybe it's because the old EF 85mm 1.2 has a particularly noisy aperture mechanism, and the fact that it is luminous exacerbates this behaviour?… I'll try your suggestion to see how it works.

Thanks!

Click to expand...

fcracer is correct in his explanation, there is nothing wrong with your camera. This aperture behavior also occurs in my other Fuji and Sony cameras. Why other users are not knowledgeable of this is curious, it is quite easy to observe.

Click to expand...

This is actually something new to me, and really bothersome I have to say. I have the Sony A7RIV with MC-11 and the same EF 85 f1,2 in my hands, and it does not send impulses to the blades as luminosity changes, but does the luminosity adjustment electronically. Maybe this is something particular to the 50S which was changed with the 100S and 50SII ? I'm still in doubt that this works as it should, for why put such constant strain on the electro-mechanic commands?

Click to expand...

The aperture behavior can also be lens dependent with faster lenses exhibiting this behavior more often.

I don't use lens adapters on my 100S so I can't help you there. Maybe if bobby350Z sees this thread (or you outreach him by private message) he can give you his direct experience. He's had your 50S and ED 85/1.2 and Sonys as well.

In you Fuji-Sony comparison you also have the complication of two different lens adapter brands. Sending it in for service or returning it may be your best course of action to put you at ease.

goodbokeh said:

alpshiker said:

goodbokeh said:

goodbokeh said:

goodbokeh said:

This is normal behaviour for a mirrorless camera. Due to the EVF, the camera needs to provide reasonable amount of light onto the sensor to feed the EVF with the proper exposure so the user has a representation of the scene through the EVF. When you go to take the exposure, the camera will shift to the selected aperture.

If it’s really bothering you, there’s a setting in the menu to “preview depth of field” which you can assign to a button. This will stop the lens down to selected aperture and that’s what will be shown in the EVF. Please note that focus speed can be impacted if you stop down too much.

Click to expand...

Oh, this explanation seems to answer the question. But why have other users not notice? Maybe it's because the old EF 85mm 1.2 has a particularly noisy aperture mechanism, and the fact that it is luminous exacerbates this behaviour?… I'll try your suggestion to see how it works.

Thanks!

Click to expand...

fcracer is correct in his explanation, there is nothing wrong with your camera. This aperture behavior also occurs in my other Fuji and Sony cameras. Why other users are not knowledgeable of this is curious, it is quite easy to observe.

Click to expand...

This is actually something new to me, and really bothersome I have to say. I have the Sony A7RIV with MC-11 and the same EF 85 f1,2 in my hands, and it does not send impulses to the blades as luminosity changes, but does the luminosity adjustment electronically. Maybe this is something particular to the 50S which was changed with the 100S and 50SII ? I'm still in doubt that this works as it should, for why put such constant strain on the electro-mechanic commands?

Click to expand...

The aperture behavior can also be lens dependent with faster lenses exhibiting this behavior more often.

I don't use lens adapters on my 100S so I can't help you there. Maybe if bobby350Z sees this thread (or you outreach him by private message) he can give you his direct experience. He's had your 50S and ED 85/1.2 and Sonys as well.

In you Fuji-Sony comparison you also have the complication of two different lens adapter brands. Sending it in for service or returning it may be your best course of action to put you at ease.

Click to expand...

Yes, maybe someone who has the same configuration will confirm. But it is not limited to the adapted lenses. The 110 f2 does the same. I'm just a little circumspect because I got the camera second hand, and I also had a strange behaviour when I used the hinge for the viewfinder that came with. Maybe something got haywire…

alpshiker said:

goodbokeh said:

alpshiker said:

goodbokeh said:

alpshiker said:

alpshiker said:

This is normal behaviour for a mirrorless camera. Due to the EVF, the camera needs to provide reasonable amount of light onto the sensor to feed the EVF with the proper exposure so the user has a representation of the scene through the EVF. When you go to take the exposure, the camera will shift to the selected aperture.

If it’s really bothering you, there’s a setting in the menu to “preview depth of field” which you can assign to a button. This will stop the lens down to selected aperture and that’s what will be shown in the EVF. Please note that focus speed can be impacted if you stop down too much.

Click to expand...

Oh, this explanation seems to answer the question. But why have other users not notice? Maybe it's because the old EF 85mm 1.2 has a particularly noisy aperture mechanism, and the fact that it is luminous exacerbates this behaviour?… I'll try your suggestion to see how it works.

Thanks!

Click to expand...

fcracer is correct in his explanation, there is nothing wrong with your camera. This aperture behavior also occurs in my other Fuji and Sony cameras. Why other users are not knowledgeable of this is curious, it is quite easy to observe.

Click to expand...

This is actually something new to me, and really bothersome I have to say. I have the Sony A7RIV with MC-11 and the same EF 85 f1,2 in my hands, and it does not send impulses to the blades as luminosity changes, but does the luminosity adjustment electronically. Maybe this is something particular to the 50S which was changed with the 100S and 50SII ? I'm still in doubt that this works as it should, for why put such constant strain on the electro-mechanic commands?

Click to expand...

The aperture behavior can also be lens dependent with faster lenses exhibiting this behavior more often.

I don't use lens adapters on my 100S so I can't help you there. Maybe if bobby350Z sees this thread (or you outreach him by private message) he can give you his direct experience. He's had your 50S and ED 85/1.2 and Sonys as well.

In you Fuji-Sony comparison you also have the complication of two different lens adapter brands. Sending it in for service or returning it may be your best course of action to put you at ease.

Click to expand...

Yes, maybe someone who has the same configuration will confirm. But it is not limited to the adapted lenses. The 110 f2 does the same. I'm just a little circumspect because I got the camera second hand, and I also had a strange behaviour when I used the hinge for the viewfinder that came with. Maybe something got haywire…

Click to expand...

Well, if the viewfinder is acting up then I would advise outreaching the seller for a return or at least covering the repair cost by Fuji. Good luck.

goodbokeh said:

Well, if the viewfinder is acting up then I would advise outreaching the seller for a return or at least covering the repair cost by Fuji. Good luck.

Click to expand...

Thanks!

Maybe it's faulty, or maybe not. If a 50S owner would confirm that this is normal before I send the body to Fuji for control, that would be helpful.

alpshiker said:

goodbokeh said:

Well, if the viewfinder is acting up then I would advise outreaching the seller for a return or at least covering the repair cost by Fuji. Good luck.

Click to expand...

Thanks!

Maybe it's faulty, or maybe not. If a 50S owner would confirm that this is normal before I send the body to Fuji for control, that would be helpful.

Click to expand...

Let me double check. I am pretty sure most Fuji GF lenses do this. Way back when GFX50s just got released, I borrowed from it from my co-worker and constant noise by 120mm f4 drove me nuts. My copy of GFX50s and 120mm f4 didn't do it. Maybe some setting I am not sure.

Using Fringer, initially my Tamron 35mm f1.8 was acting up a lot. After firmware update none of that.

Sony don't do as much as most people shoot Sony in AF-C mode and in AF-C mode, lenses focus at shooting apertures.

bobby350z said:

alpshiker said:

goodbokeh said:

Well, if the viewfinder is acting up then I would advise outreaching the seller for a return or at least covering the repair cost by Fuji. Good luck.

Click to expand...

Thanks!

Maybe it's faulty, or maybe not. If a 50S owner would confirm that this is normal before I send the body to Fuji for control, that would be helpful.

Click to expand...

Let me double check. I am pretty sure most Fuji GF lenses do this. Way back when GFX50s just got released, I borrowed from it from my co-worker and constant noise by 120mm f4 drove me nuts. My copy of GFX50s and 120mm f4 didn't do it. Maybe some setting I am not sure.

Using Fringer, initially my Tamron 35mm f1.8 was acting up a lot. After firmware update none of that.

Sony don't do as much as most people shoot Sony in AF-C mode and in AF-C mode, lenses focus at shooting apertures.

Click to expand...

Oh please! That will be helpful.

I updated the firmwares a month ago.

alpshiker said:

bobby350z said:

alpshiker said:

goodbokeh said:

Well, if the viewfinder is acting up then I would advise outreaching the seller for a return or at least covering the repair cost by Fuji. Good luck.

Click to expand...

Thanks!

Maybe it's faulty, or maybe not. If a 50S owner would confirm that this is normal before I send the body to Fuji for control, that would be helpful.

Click to expand...

Let me double check. I am pretty sure most Fuji GF lenses do this. Way back when GFX50s just got released, I borrowed from it from my co-worker and constant noise by 120mm f4 drove me nuts. My copy of GFX50s and 120mm f4 didn't do it. Maybe some setting I am not sure.

Using Fringer, initially my Tamron 35mm f1.8 was acting up a lot. After firmware update none of that.

Sony don't do as much as most people shoot Sony in AF-C mode and in AF-C mode, lenses focus at shooting apertures.

Click to expand...

Oh please! That will be helpful.

I updated the firmwares a month ago.

Click to expand...

I was able to reproduce it on my GFX50s as well as GFX100s. I used 3 lenses, 110mm f2, 80mm f1.7 and Canon 200mm f2.8 with Fringer adapter. The opening/closing of the aperture blades happens as you point camera at dark or bright scene. It happens in AF-S, as well as in AF-C mode. Not in Manual Focus mode.

It is the Preview Exposure In Manual Mode setting. If set to OFF so that you can see an amplified view of the scene like when shooting inside. In this case, camera adjusts the aperture based on where it is being pointed. If you disable this feature (so Preview is ON, so that if you stop down or increase ss, the EVF will get daker), then this chattering stops.

Now one strange thing, 80mm f1.7 chatters on GFX50s but on GFX100s it was the only lens which didn't do chattering. Not sure why. I had aperture set to f1.7.

My case I shoot inside studio as well as outside. This Preview On/Off has bit me quite a few times as it gives wrong histogram as well as preview in EVF of what the shot will look like. Most shoots, I will double check by stopping down aperture and making sure EVF gets darker to know which mode I am currently in. I will even do the old dSLR thing of taking the shot and review it later to make sure mode is set correctly.