X-Pro 1: No exposure compensation in Auto-ISO - is this a bug?

Started Feb 5, 2013 | Discussions
tee1000
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X-Pro 1: No exposure compensation in Auto-ISO - is this a bug?
Feb 5, 2013

Hello folks,

my standard setting on my X Pro 1 is:
- manual apperture
- manual shutter speed
- Auto-ISO

This gives me best creative control while still having an exposure automation with the Auto-ISO. But the camera calls this M/manual, so the exposure compensation is being ignored.

This is strange and non sense, as the camera always chooses the ISO to match EV 0.

What's the point of this?

Thanks
Tobias

mngsmt
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Re: X-Pro 1: No exposure compensation in Auto-ISO - is this a bug?
In reply to tee1000, Feb 5, 2013

tee1000 wrote:

Hello folks,

my standard setting on my X Pro 1 is:
- manual apperture
- manual shutter speed
- Auto-ISO

This gives me best creative control while still having an exposure automation with the Auto-ISO. But the camera calls this M/manual, so the exposure compensation is being ignored.

This is strange and non sense, as the camera always chooses the ISO to match EV 0.

What's the point of this?

According to some, that's a feature.

Seriously though, that''s just the way it is for now. Some of us are still hoping it's fixable with a firmware update.

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TThorne
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Re: X-Pro 1: No exposure compensation in Auto-ISO - is this a bug?
In reply to tee1000, Feb 5, 2013

Didn't you know? There are no bugs, mistakes, shortcomings, or errors EVER, by Fuji on any Fuji products. You should be bound and stoned for even suggesting such a thing! I am repulsed and dismayed at your ignorance! Go buy another camera!

All joking aside now... I see that this is your first post so you may not get the inside joke, but I feel your frustration. It is a bit absurd to not have EC control in M mode. That mixed with no minimum shutter in auto ISO and it seems they set out on purpose to cripple the system. I am hoping for a firmware fix of both or at least one.

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Jeff Charles
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It is a shortcoming
In reply to tee1000, Feb 5, 2013

Auto exposure should always have exposure compensation.

For example, in this case, the camera's AE system may choose an ISO that pushes highlights into clipping. The photographer needs to be able to set negative EC to prevent that.

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Jeff
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Re: X-Pro 1: No exposure compensation in Auto-ISO - is this a bug?
In reply to tee1000, Feb 6, 2013

It is not a bug or oversight. In manual exposure mode you manually adjust the aperture and/or the shutter speed to change exposure with your fingers. The using the EC dial is redundant and unnecessary.

You are confusing exposure with ISO. Only shutter speed and aperture determine exposure. In digital cameras ISO just changes the exposure index. Changing ISO lets you use higher or lower shutter speed and aperture combinations. But the only the shutter and aperture control  how much light reaches the sensor. ISO does not change how many photons are converted to voltage at each sensor site. ISO multiples the actual photon counts either  electronically or mathematically so in-camera jpeg rendering is convenient. ISO does not not make the sensor more, or less efficient.  It appears  to change the sensor efficiency  so the photographer  enjoys more flexibility.

This is explained here

http://www.luminous-landscape.com/essays/dxomark_sensor_for_benchmarking_cameras2.shtml

but you have to scroll down to the last third if this very long article.

Auto ISO is useful. If you want to keep the shutter speed fixed to freeze motion and also maintain a constant DOF, then Auto ISO is a convenience - you don't need to go into the menus to change the exposure index.

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nixda
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Re: X-Pro 1: No exposure compensation in Auto-ISO - is this a bug?
In reply to wchutt, Feb 6, 2013

wchutt wrote:

It is not a bug or oversight. In manual exposure mode you manually adjust the aperture and/or the shutter speed to change exposure with your fingers. The using the EC dial is redundant and unnecessary.

You are confusing exposure with ISO. Only shutter speed and aperture determine exposure. In digital cameras ISO just changes the exposure index. Changing ISO lets you use higher or lower shutter speed and aperture combinations. But the only the shutter and aperture control how much light reaches the sensor. ISO does not change how many photons are converted to voltage at each sensor site. ISO multiples the actual photon counts either electronically or mathematically so in-camera jpeg rendering is convenient. ISO does not not make the sensor more, or less efficient. It appears to change the sensor efficiency so the photographer enjoys more flexibility.

This is explained here

http://www.luminous-landscape.com/essays/dxomark_sensor_for_benchmarking_cameras2.shtml

but you have to scroll down to the last third if this very long article.

Auto ISO is useful. If you want to keep the shutter speed fixed to freeze motion and also maintain a constant DOF, then Auto ISO is a convenience - you don't need to go into the menus to change the exposure index.

Although you are formally correct in that 'exposure' is determined by aperture and shutter speed, there are plenty of renowned photographers and photography websites who consider ISO part of the exposure 'triangle'. The point is that the intensity values written to the RAW or JPEG file depend not only on aperture and shutter speed but also on ISO, and the intensity values is what one would like to affect when carrying out exposure compensation.

So let's call it something other than 'exposure' compensation, and we can actually get to the point of the OP's complaint, namely, that there isn't a way to adjust ISO when the camera chooses a value that is not 'correct'. In the other Auto modes (shutter speed and aperture) there is a way, so there also should be one for Auto-ISO. And the EC dial is perfectly suited for that purpose and not at all redundant or unnecessary. The post by Jeff Charles points out very nicely why that is the case.

Bottom line, it's not a bug but a design choice. And a pretty bad one, judging by the current commotion over this feature. It would be so easy to allow adjusting the ISO with the EC dial, and everybody would be happy.

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JasperD
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Re: X-Pro 1: No exposure compensation in Auto-ISO - is this a bug?
In reply to TThorne, Feb 6, 2013

If only one of the two, I sure hope it´s Exposure Compensation for AutoISO in so called Manual... I´m not a potential user of minimum shutter speed, I set it myself to a fixed value with the wheel, according to subject.

However, if Fuji listens to its users, it should give both IMO; it seems quite doable. I´m still hoping for improvement, indeed.

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TThorne
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Re: X-Pro 1: No exposure compensation in Auto-ISO - is this a bug?
In reply to JasperD, Feb 6, 2013

JasperD wrote:

If only one of the two, I sure hope it´s Exposure Compensation for AutoISO in so called Manual... I´m not a potential user of minimum shutter speed, I set it myself to a fixed value with the wheel, according to subject.

However, if Fuji listens to its users, it should give both IMO; it seems quite doable. I´m still hoping for improvement, indeed.

While I agree with you, I'd like to see the histogram and expanded DR modes work in Manual mode as well.

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JasperD
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Re: X-Pro 1: No exposure compensation in Auto-ISO - is this a bug?
In reply to TThorne, Feb 6, 2013

You will not read me objecting to any additional features, as long as they provide more options (so are not of mandatory use). However, Exposure Compensation with AutoISO in ´Manual´ has been the one line highest on my own wish list since March 19th. 2012, day of purchase of my X-Pro1; so it makes sense for me, I´d like that to be of highest priority too. A very personal opinion, of course.

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TThorne
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Re: X-Pro 1: No exposure compensation in Auto-ISO - is this a bug?
In reply to JasperD, Feb 6, 2013

JasperD wrote:

You will not read me objecting to any additional features, as long as they provide more options (so are not of mandatory use). However, Exposure Compensation with AutoISO in ´Manual´ has been the one line highest on my own wish list since March 19th. 2012, day of purchase of my X-Pro1; so it makes sense for me, I´d like that to be of highest priority too. A very personal opinion, of course.

I think a lot of people share that opinion with you, me included. Makes total sense to me.

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Re: X-Pro 1: No exposure compensation in Auto-ISO - is this a bug?
In reply to nixda, Feb 6, 2013

nixda wrote:


Although you are formally correct in that 'exposure' is determined by aperture and shutter speed, there are plenty of renowned photographers and photography websites who consider ISO part of the exposure 'triangle'. The point is that the intensity values written to the RAW or JPEG file depend not only on aperture and shutter speed but also on ISO, and the intensity values is what one would like to affect when carrying out exposure compensation.

Renowned  photographers consistently deliver quality images in a business-like fashion. They are very good at marketing themselves. This doesn't mean they understand the physics of digital training.

The exposure triangle is: light, shutter speed and aperture. Sensor-signal amplification has nothing to do with exposure.

Writers at renowned websites should know better. Unfortunately even renowned web sites do not spend money employing fact checkers or consultants to insure their content is accurate.

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mngsmt
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Re: X-Pro 1: No exposure compensation in Auto-ISO - is this a bug?
In reply to wchutt, Feb 6, 2013

wchutt wrote:

It is not a bug or oversight. In manual exposure mode you manually adjust the aperture and/or the shutter speed to change exposure with your fingers. The using the EC dial is redundant and unnecessary.

It's neither redundant nor unnecessary. It's simply convenient.

You are confusing exposure with ISO. Only shutter speed and aperture determine exposure. In digital cameras ISO just changes the exposure index. Changing ISO lets you use higher or lower shutter speed and aperture combinations. But the only the shutter and aperture control how much light reaches the sensor. ISO does not change how many photons are converted to voltage at each sensor site. ISO multiples the actual photon counts either electronically or mathematically so in-camera jpeg rendering is convenient. ISO does not not make the sensor more, or less efficient. It appears to change the sensor efficiency so the photographer enjoys more flexibility.

This is a very theoretical, very un-practical approach and I won't argue with these "facts". It's just that I'm of the opinion that when the camera changes anything automatically which affects the exposure of the final image (call it brightness if you wish), the user should have the option to override the camera's setting.

Auto ISO is useful. If you want to keep the shutter speed fixed to freeze motion and also maintain a constant DOF, then Auto ISO is a convenience - you don't need to go into the menus to change the exposure index.

Absolutely. Unfortunately, as it is now, you have to go into the menu to change the brightness/exposure/ISO and the exposure compensation dial sits idle, does nothing and is bored to death.

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mjl699
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Re: X-Pro 1: No exposure compensation in Auto-ISO - is this a bug?
In reply to wchutt, Feb 6, 2013

wchutt wrote:

nixda wrote:


Although you are formally correct in that 'exposure' is determined by aperture and shutter speed, there are plenty of renowned photographers and photography websites who consider ISO part of the exposure 'triangle'. The point is that the intensity values written to the RAW or JPEG file depend not only on aperture and shutter speed but also on ISO, and the intensity values is what one would like to affect when carrying out exposure compensation.

Renowned photographers consistently deliver quality images in a business-like fashion. They are very good at marketing themselves. This doesn't mean they understand the physics of digital training.

The exposure triangle is: light, shutter speed and aperture. Sensor-signal amplification has nothing to do with exposure.

Writers at renowned websites should know better. Unfortunately even renowned web sites do not spend money employing fact checkers or consultants to insure their content is accurate.

wchutt :: Although technically what you say might be correct what you say is not the full picture.

We now have a situation where the sensor amplification can be selected in the same way as aperture and shutter speed. Amplification changes the sensitivity of the sensor to incident light. Higher amplification results in higher sensitivity. This is termed and related (somewhat loosely at times) to ISO values which are also about sencitivity to light.

Amplification relates to sensitivity to light, ISO for film relates to sensitivity to light. The term ISO in modern digital cameras as related to amplification is a reasonable analogy to speed in film-based photogrpahy which were rated using ISO.

Even in the days of film, using a faster film meant a reduction in the required exposure to get a "correctly exposed" image. So even then, film speed did impact exposure, even if not technically part of exposure.

What I mean when I say I want exposure comp in manual mode is the following: Say I want to shoot at F2.0, T=1/60s, and I am using AutoISO 1600. The camera exposes for the "correct" exposure as measured by the in camera meter, choosing ISO 800. I want to achieve the result of underexposing by one stop. My options are: (1) Use F/2.8; (2) Use T=1/120s; (3) cheat and use ISO 400 (nice not to have to change films to do this). In each case the result should be the same - I should record half the count from each pixel on the sensor. I want the option to stick with F/2.0, T=1/120s, and instead of fiddling around to set ISO=400, I just want to set EC=-1 and let the camera work out the required ISO setting to produce an image with half the count (i.e. exactly the same as darker by 1 stop) than its meters would normally achieve by choosing the ISO to give the "correct" exposure.

This is what we are all meaning when we say we want EC to work in Manual Mode with AutoISO.

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mjl599

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nixda
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Re: X-Pro 1: No exposure compensation in Auto-ISO - is this a bug?
In reply to mjl699, Feb 6, 2013

mjl699 wrote:

wchutt wrote:

nixda wrote:


Although you are formally correct in that 'exposure' is determined by aperture and shutter speed, there are plenty of renowned photographers and photography websites who consider ISO part of the exposure 'triangle'. The point is that the intensity values written to the RAW or JPEG file depend not only on aperture and shutter speed but also on ISO, and the intensity values is what one would like to affect when carrying out exposure compensation.

Renowned photographers consistently deliver quality images in a business-like fashion. They are very good at marketing themselves. This doesn't mean they understand the physics of digital training.

The exposure triangle is: light, shutter speed and aperture. Sensor-signal amplification has nothing to do with exposure.

Writers at renowned websites should know better. Unfortunately even renowned web sites do not spend money employing fact checkers or consultants to insure their content is accurate.

wchutt :: Although technically what you say might be correct what you say is not the full picture.

We now have a situation where the sensor amplification can be selected in the same way as aperture and shutter speed. Amplification changes the sensitivity of the sensor to incident light. Higher amplification results in higher sensitivity. This is termed and related (somewhat loosely at times) to ISO values which are also about sencitivity to light.

Amplification relates to sensitivity to light, ISO for film relates to sensitivity to light. The term ISO in modern digital cameras as related to amplification is a reasonable analogy to speed in film-based photogrpahy which were rated using ISO.

Even in the days of film, using a faster film meant a reduction in the required exposure to get a "correctly exposed" image. So even then, film speed did impact exposure, even if not technically part of exposure.

What I mean when I say I want exposure comp in manual mode is the following: Say I want to shoot at F2.0, T=1/60s, and I am using AutoISO 1600. The camera exposes for the "correct" exposure as measured by the in camera meter, choosing ISO 800. I want to achieve the result of underexposing by one stop. My options are: (1) Use F/2.8; (2) Use T=1/120s; (3) cheat and use ISO 400 (nice not to have to change films to do this). In each case the result should be the same - I should record half the count from each pixel on the sensor. I want the option to stick with F/2.0, T=1/120s, and instead of fiddling around to set ISO=400, I just want to set EC=-1 and let the camera work out the required ISO setting to produce an image with half the count (i.e. exactly the same as darker by 1 stop) than its meters would normally achieve by choosing the ISO to give the "correct" exposure.

This is what we are all meaning when we say we want EC to work in Manual Mode with AutoISO.

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mjl599

Correct.

Another way to to put it: in order to get an image, one needs light and a sensing medium. Light is controlled by aperture, shutter speed (and the light of the scene, of course). The sensing medium in our case is a sensor, and its response to light is controlled by adjusting ISO. All of those have an effect on the final image and thus, one needs to be able to adjust them quickly and reliably.

Just picture ISO to be a set of film rolls preloaded into the camera. When Auto-ISO choses one that isn't the right one for a given situation, it should be possible to override the camera and switch to a different film, so to say. Just like in the old days, but much faster.

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nixda
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Re: X-Pro 1: No exposure compensation in Auto-ISO - is this a bug?
In reply to wchutt, Feb 6, 2013

wchutt wrote:

It is not a bug or oversight. In manual exposure mode you manually adjust the aperture and/or the shutter speed to change exposure with your fingers. The using the EC dial is redundant and unnecessary.

You are confusing exposure with ISO. Only shutter speed and aperture determine exposure. In digital cameras ISO just changes the exposure index. Changing ISO lets you use higher or lower shutter speed and aperture combinations. But the only the shutter and aperture control how much light reaches the sensor. ISO does not change how many photons are converted to voltage at each sensor site. ISO multiples the actual photon counts either electronically or mathematically so in-camera jpeg rendering is convenient. ISO does not not make the sensor more, or less efficient. It appears to change the sensor efficiency so the photographer enjoys more flexibility.

This is explained here

http://www.luminous-landscape.com/essays/dxomark_sensor_for_benchmarking_cameras2.shtml

but you have to scroll down to the last third if this very long article.

Auto ISO is useful. If you want to keep the shutter speed fixed to freeze motion and also maintain a constant DOF, then Auto ISO is a convenience - you don't need to go into the menus to change the exposure index.

Here is the behavior on the X-E1. I don't have an X-Pro1, so someone who has one needs to check this:

When Auto-ISO is selected in shutter-priority mode, EV Compensation through the EC dial changes aperture; when ISO is maxed out, then ISO changes.

When Auto-ISO is selected in aperture-priority mode, EV Compensation through the EC dial changes ISO, not shutter speed; when ISO is maxed out, then shutter speed changes.

When Auto-ISO is selected in manual mode, EV Compensation through the EC dial changes nothing.

So in fact, Fuji already allows ISO compensation through the EC dial, but only in aperture-priority mode.

This behavior is inconsistent, at best, and not what one would necessarily want. For example, when shooting HDR (in aperture priority), one would need to remember to set the ISO explicitly. Fair enough. It could be that Fuji is so confident in their sensor that they thought it would be acceptable to ramp up ISO before reducing shutter speed. However, in shutter priority, they thought it would be perfectly fine to have the EC dial adjust the aperture.

Go figure.
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jondh
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Re: X-Pro 1: No exposure compensation in Auto-ISO - is this a bug?
In reply to tee1000, Feb 6, 2013

Off course it is like that. Auto ISO is used with the purpose of getting better ISO based on the available exposure not to change the exposure of the manual mode.

Do you expect that if you increase exposure compensation, for example, from EV0 to EV-1 the photo will be darker because ISO change from 400 to 200?

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Jeff Charles
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Re: X-Pro 1: No exposure compensation in Auto-ISO - is this a bug?
In reply to jondh, Feb 6, 2013

jondh wrote:

Off course it is like that. Auto ISO is used with the purpose of getting better ISO based on the available exposure not to change the exposure of the manual mode.

Right. ISO cannot change exposure. Only aperture and shutter speed can do that.

Do you expect that if you increase exposure compensation, for example, from EV0 to EV-1 the photo will be darker because ISO change from 400 to 200?

Yes. Assuming no change in exposure, increasing ISO makes the photo brighter, and decreasing ISO makes the photo darker.

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mngsmt
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Re: X-Pro 1: No exposure compensation in Auto-ISO - is this a bug?
In reply to Jeff Charles, Feb 6, 2013

Jeff Charles wrote:

jondh wrote:

Off course it is like that. Auto ISO is used with the purpose of getting better ISO based on the available exposure not to change the exposure of the manual mode.

Right. ISO cannot change exposure. Only aperture and shutter speed can do that.

Although maybe technically correct, I think this is nitpicking. The amount of amplification applied by the camera is definitely part of the equation for calculating the "exposure".

Think of a variable ND filter that sits in front of the sensor, for example. The fact that the signal amplification (aka ISO) sits kind of "behind the sensor" is not really important in practice.

Do you expect that if you increase exposure compensation, for example, from EV0 to EV-1 the photo will be darker because ISO change from 400 to 200?

Yes. Assuming no change in exposure, increasing ISO makes the photo brighter, and decreasing ISO makes the photo darker.

Yes. That's what Auto ISO should provide. A means to manually change the brightness of the resulting photo. As any other automated exposure mode does.

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hellocrowley
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Re: X-Pro 1: No exposure compensation in Auto-ISO - is this a bug?
In reply to Jeff Charles, Feb 6, 2013

Jeff Charles wrote:

jondh wrote:

Off course it is like that. Auto ISO is used with the purpose of getting better ISO based on the available exposure not to change the exposure of the manual mode.

Right. ISO cannot change exposure. Only aperture and shutter speed can do that.

When your aperture and shutter speed are fixed, what do you do to get a correctly exposed photo? Do you change the ISO value?

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tee1000
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Re: X-Pro 1: No exposure compensation in Auto-ISO - is this a bug?
In reply to mjl699, Feb 6, 2013

mjl699 wrote:

wchutt wrote:

nixda wrote:


Although you are formally correct in that 'exposure' is determined by aperture and shutter speed, there are plenty of renowned photographers and photography websites who consider ISO part of the exposure 'triangle'. The point is that the intensity values written to the RAW or JPEG file depend not only on aperture and shutter speed but also on ISO, and the intensity values is what one would like to affect when carrying out exposure compensation.

Renowned photographers consistently deliver quality images in a business-like fashion. They are very good at marketing themselves. This doesn't mean they understand the physics of digital training.

The exposure triangle is: light, shutter speed and aperture. Sensor-signal amplification has nothing to do with exposure.

Writers at renowned websites should know better. Unfortunately even renowned web sites do not spend money employing fact checkers or consultants to insure their content is accurate.

wchutt :: Although technically what you say might be correct what you say is not the full picture.

We now have a situation where the sensor amplification can be selected in the same way as aperture and shutter speed. Amplification changes the sensitivity of the sensor to incident light. Higher amplification results in higher sensitivity. This is termed and related (somewhat loosely at times) to ISO values which are also about sencitivity to light.

Amplification relates to sensitivity to light, ISO for film relates to sensitivity to light. The term ISO in modern digital cameras as related to amplification is a reasonable analogy to speed in film-based photogrpahy which were rated using ISO.

Even in the days of film, using a faster film meant a reduction in the required exposure to get a "correctly exposed" image. So even then, film speed did impact exposure, even if not technically part of exposure.

What I mean when I say I want exposure comp in manual mode is the following: Say I want to shoot at F2.0, T=1/60s, and I am using AutoISO 1600. The camera exposes for the "correct" exposure as measured by the in camera meter, choosing ISO 800. I want to achieve the result of underexposing by one stop. My options are: (1) Use F/2.8; (2) Use T=1/120s; (3) cheat and use ISO 400 (nice not to have to change films to do this). In each case the result should be the same - I should record half the count from each pixel on the sensor. I want the option to stick with F/2.0, T=1/120s, and instead of fiddling around to set ISO=400, I just want to set EC=-1 and let the camera work out the required ISO setting to produce an image with half the count (i.e. exactly the same as darker by 1 stop) than its meters would normally achieve by choosing the ISO to give the "correct" exposure.

This is what we are all meaning when we say we want EC to work in Manual Mode with AutoISO.

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mjl599

Dear wchutt.
you are right in general, but I think you missed the point of auto-ISO. Of course I can change ISO in manual mode to alter the exposure. But what does auto-ISO do? It selects the ISO to match camera's EV0 measurement. So I think it is just a software issue to let the camera choose ISO for -let's say- EV-1.

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