AUTO ISO

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Use exposure compensation. When the background is brighter you most often would brighten (positive exposure compensation). When the background is darker, you would usually darken (negative exposure compensation.) If you have blinkies/overexposure warning you can take some test shots to find what level of compensation gets you the brightest image without the blinkies flashing. Or look at the histogram and get as close to the right wall as you can without climbing up the wall even a little.

Rule of thumb: background brighter - brighten, background darker - darken. The reason this seems backwards is that when the meter sees mostly very dark it wants to pull it up too much to the middle, so you compensate by moving it back darker. When the meter sees mostly bright it wants to pull it down to the middle, so you compensate by brightening/adding exposure.
Thank you I can understand what you say.
 
My settings are. ISO Sensitivity 64, Sensitivity ON Max 12800, Minimum 1000, Manual Mode
The problem seems to be the minimum ISO setting, which is much to high when in auto ISO. Even if you have had the ISO set to 64 manualy before.
Together with the normaly to slow shutter speed of 1/200, it's no wonder that your picture is overexposed. The minimum ISO should be set to100, or even 64.
Together with a shutterspeed set to 1/1250 or even 1/2000 your problem should be solved and you can open up your aperture.
 
This may be more anecdotal than helpful, but for the first time I had an auto ISO issue while I was in Costa Rica. I never used auto ISO, always manual, so I repurposed the exp. compensation button. In CR, there was so much switching lighting conditions with fast moving birds, that I decided to use it. And much of the time, it would over-or-under expose. Since I couldn't use the exp. comp feature, I would read the value it applied to a correct image, and switch to manual using that value. Cumbersome and missed some shots, but it worked.
 
I shoot with a sony A1, any good info on this camera with auto Iso Steve ? On the settings inside of the camera..
thank You
I think the problem is that people are mentally bifurcating Auto ISO and metering as if Auto ISO has its own metering method and it doesn't (you'll see this in several of the posts here). When people say Auto ISO overexposes, underexposes, etc, that NOT the case and never is. The meter is over or under exposing and instead of using shutter speed or aperture to do it, it's using ISO. That's the only difference. If you were to set the camera for auto exposure in any other mode, you'd get the same amount of over / under exposure, etc.

So, nope, nothing specific or special for Auto ISO with the Sony (or any camera) it's just doing what the meter tells it :)

Also, welcome to the forums :)
 
I think the problem is that people are mentally bifurcating Auto ISO and metering as if Auto ISO has its own metering method and it doesn't (you'll see this in several of the posts here). When people say Auto ISO overexposes, underexposes, etc, that NOT the case and never is. The meter is over or under exposing and instead of using shutter speed or aperture to do it, it's using ISO. That's the only difference. If you were to set the camera for auto exposure in any other mode, you'd get the same amount of over / under exposure, etc.

So, nope, nothing specific or special for Auto ISO with the Sony (or any camera) it's just doing what the meter tells it :)

Also, welcome to the forums :)
Thanks so much Steve
 
Per the setting you described, I think your minimum is set to ISO 1000. In Auto ISO mode your camera won’t shoot below the minimum, so the camera is probably hitting max shutter speed and still over exposing. Try setting your minimum to 64 for bright sun and then move up for darker settings. I tend to use Auto ISO for a max, then manually bump up the actual ISO when it is a dim setting.

If you also use electronic first curtain shutter, some cameras restrict max shutter speed to 1/2000, which would make overexposure even more likely.

In bright sun you might be shooting at ISO 1000, 1/2000, f16 with current settings. You’d probably want to be closer to f/16, ISO64, 1/500.
 
Per the setting you described, I think your minimum is set to ISO 1000. In Auto ISO mode your camera won’t shoot below the minimum, so the camera is probably hitting max shutter speed and still over exposing. Try setting your minimum to 64 for bright sun and then move up for darker settings. I tend to use Auto ISO for a max, then manually bump up the actual ISO when it is a dim setting.

If you also use electronic first curtain shutter, some cameras restrict max shutter speed to 1/2000, which would make overexposure even more likely.

In bright sun you might be shooting at ISO 1000, 1/2000, f16 with current settings. You’d probably want to be closer to f/16, ISO64, 1/500.
Are you talking about Z9 ? ... there is no minimum iso setting in auto ISO only minimum shutter speed. Since there is no mechanical shutter in a Z9 it seems you are talking about flash sync settings? Or referring to something other than a Z9 which is what the OP is asking about.
 
Per the setting you described, I think your minimum is set to ISO 1000. In Auto ISO mode your camera won’t shoot below the minimum, so the camera is probably hitting max shutter speed and still over exposing. Try setting your minimum to 64 for bright sun and then move up for darker settings. I tend to use Auto ISO for a max, then manually bump up the actual ISO when it is a dim setting.

If you also use electronic first curtain shutter, some cameras restrict max shutter speed to 1/2000, which would make overexposure even more likely.

In bright sun you might be shooting at ISO 1000, 1/2000, f16 with current settings. You’d probably want to be closer to f/16, ISO64, 1/500.

Canons can set an iso range including a minimum and maximum, but I don't think the OP's camera has that option.
 
This may be more anecdotal than helpful, but for the first time I had an auto ISO issue while I was in Costa Rica. I never used auto ISO, always manual, so I repurposed the exp. compensation button. In CR, there was so much switching lighting conditions with fast moving birds, that I decided to use it. And much of the time, it would over-or-under expose. Since I couldn't use the exp. comp feature, I would read the value it applied to a correct image, and switch to manual using that value. Cumbersome and missed some shots, but it worked.
You can use eposure compensation in mauell with auto-iso. It works perfectly fine.
 
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