Auto ISO Behavior

Hello all, I have been using auto ISO here and there to see what all the fuss is about.  I have been really pleased with it and generally top the ISO out at 6400.  I have found that it appears to raise the ISO before it raises the shutter speed.  When I have my 23mm on, I have the settings at Base ISO - 200, ISO Limit - 6400, and shutter at 1/60th.  In bright daylight, the shutter will stay at 1/60th and the ISO will be up over 1000 at times.  Isn't the ISO supposed to stay at the base and only raise when the shutter is at the limit?

Am I not understanding how auto ISO is supposed to work?  It is very frustrating, thinking that I'm going to get a certain SS and then notice the ISO has gone up instead of the shutter.  I end up going back to manual ISO, I'm just wondering if there is something I am missing in the equation.

Thanks!

Jeff

You definitely have a weird setting enabled or something. What camera are you using? In my X-H1 the settings were pretty simple to figure out. Be aware that DR200 and DR400 will do weird things with auto ISO.

Auto-ISO will raise the ISO only if your minimum shutter speed has been reached. The camera will however typically display your max ISO setting unless the exposure is locked (with a half-press).

If your camera raised the ISO, is the shutter speed at your minimum setting? If so, it did what it was supposed to do, the only other options are to lower the shutter speed below you minimum setting (which you DON’T want) or to increase the aperture setting (which, I assume you are controlling manually). If you have a small aperture set (higher number), the ISO can easily go over 1000.

Note: the camera will override your minimum SS setting if your max ISO limit is reached (I always use ISO 12800 for all three presets with different minimum shutter speed options).

DR200 and 400 will raise the minimum ISO available to 400 and 800 respectively.

frostyj75 wrote:

Hello all, I have been using auto ISO here and there to see what all the fuss is about. I have been really pleased with it and generally top the ISO out at 6400. I have found that it appears to raise the ISO before it raises the shutter speed. When I have my 23mm on, I have the settings at Base ISO - 200, ISO Limit - 6400, and shutter at 1/60th. In bright daylight, the shutter will stay at 1/60th and the ISO will be up over 1000 at times. Isn't the ISO supposed to stay at the base and only raise when the shutter is at the limit?

Am I not understanding how auto ISO is supposed to work? It is very frustrating, thinking that I'm going to get a certain SS and then notice the ISO has gone up instead of the shutter. I end up going back to manual ISO, I'm just wondering if there is something I am missing in the equation.

Thanks!

Jeff

To be very honest, I do not really understand what you try to explain...!

In the Auto ISO function you set

- the ISO default sensitivity, means the min ISO value you allow

- the ISO max. sensitivity, means the max ISO value you allow

- the min shutter speed

If the exposure changes, considering aperture and and other settings stay fix,

- the camera will select faster shutter speeds with the ISO at its set default sensitivity

when the scene gets brighter or

- the camera will select slower shutter speeds until it reaches the set min shutter speed at the set ISO default sensitivity

- then increase ISO until it reaches the set ISO max sensitivity at the set min shutter speed

- finally even select lower shutter speeds than the set min shutter speed when the ISO value is at the set max value

when the scene gets darker.

Also, why would the camera raise shutter speed instead of ISO? That's not not going to happen! If at all it can lower the shutter speed instead of raising ISO, but all within the boundaries you set in the Auto ISO function, as explained above.

Herbert

Hi,

I'm going to be controversial and ask 'why switch to auto-ISO?'  It doesn't seem to me to offer any significant benefits.  It introduces more complexity than setting ISO myself and occasional hidden pitfalls for the unwary.  Despite many threads on the subject, I still don't know why anyone bothers.

The Fuji gods put a thumping great knob on the top left hand end of my camera to control ISO in a system where their market purports to actually like analogue controls.  It's got numbers on it.  When the light is bright, I turn it to low numbers.  When the light is low (or I specifically want faster SS's) I turn it to higher numbers.  It's easy.  The light never changes so fast that I need it automated.  I knowwhat my camera is set to and I don't get any strange outcomes around the set-up parameters, DR management or electronic flash usage.  It's kind of fail-safe - it works beautifully!  

Cheers, Rod

Rod McD wrote:

Hi,

I'm going to be controversial and ask 'why switch to auto-ISO?' It doesn't seem to me to offer any significant benefits. It introduces more complexity than setting ISO myself and occasional hidden pitfalls for the unwary. Despite many threads on the subject, I still don't know why anyone bothers.

The Fuji gods put a thumping great knob on the top left hand end of my camera to control ISO in a system where their market purports to actually like analogue controls. It's got numbers on it. When the light is bright, I turn it to low numbers. When the light is low (or I specifically want faster SS's) I turn it to higher numbers. It's easy. The light never changes so fast that I need it automated. I knowwhat my camera is set to and I don't get any strange outcomes around the set-up parameters, DR management or electronic flash usage. It's kind of fail-safe - it works beautifully!

Cheers, Rod

I get where you're coming from, and when you're in an environment with consistent lighting, then setting ISO using the dial will serve you just fine. If you're going in and out of light, or in fast, dynamic situations, it's very nice to have ISO set to auto and have the peace of mind that you won't have any shots with shutter speeds that are too slow. Hasn't it ever happened to you when you see a fleeting moment, and bring the viewfinder to your eye, frame the scene well, take the photo, only to find that the image is blurred because shutter speed was too low? When used correctly, there are no pitfalls with auto ISO, which is kind of the point. Whenever I have used auto ISO, it has always been flawless.

Does that ISO value greater than 1000 appear only in the camera or also in the EXIF ​​data of the photos you take?

I remember that Fuji sometimes had an error between the ISO that appears on the camera (with automatic ISO) and the actual ISO with which he takes the picture.

frostyj75 wrote:

I have the settings at Base ISO - 200, ISO Limit - 6400, and shutter at 1/60th. In bright daylight, the shutter will stay at 1/60th and the ISO will be up over 1000 at times. Isn't the ISO supposed to stay at the base and only raise when the shutter is at the limit?

Are you setting the shutter speed via the dial, or setting it to 'A' alongside ISO (creating 'aperture priority' mode)

A shutter speed (or any setting) set manually on a dial will never be overridden by the camera.

Rod McD wrote:

Hi,

I'm going to be controversial and ask 'why switch to auto-ISO?' It doesn't seem to me to offer any significant benefits. It introduces more complexity than setting ISO myself and occasional hidden pitfalls for the unwary. Despite many threads on the subject, I still don't know why anyone bothers.

The Fuji gods put a thumping great knob on the top left hand end of my camera to control ISO in a system where their market purports to actually like analogue controls. It's got numbers on it. When the light is bright, I turn it to low numbers. When the light is low (or I specifically want faster SS's) I turn it to higher numbers. It's easy. The light never changes so fast that I need it automated. I knowwhat my camera is set to and I don't get any strange outcomes around the set-up parameters, DR management or electronic flash usage. It's kind of fail-safe - it works beautifully!

Cheers, Rod

Why? Because it can be set to do the same thing automatically that I would otherwise have to do manually, and it does it instantly and precisely. I am free to think about more important creative concerns like composition and aperture etc. (or I can just be lazier without screwing anything up).

There are exceptions, but most of the time one of my Auto-ISO preset minimum shutter speeds will suffice for my purposes - always maintaining a SS that's fast enough to avoid motion blur while always keeping the ISO as low as possible no matter what light I find myself in. All I have to worry about, in almost any situation, and without having to mess with any top dials or dive into any menus, is simply focusing and composing my image while tweaking the exposure/ISO as needed with my finger on the front dial (EC), period. With this arrangement I can walk from blazing sunshine and into a cave, shooting with optimal exposure the whole time without missing a beat or having to change any settings at all.

If, for some reason, I want a fixed ISO (maybe I put my camera on a tripod), I simply look down and turn the ISO dial from “A” to 200 (or whatever) …and I’m still in normal aperture priority mode.

If I need an especially high SS (maybe a hummingbird appears), I simply look down and turn the SS dial from “A” to 1/2000” (or more often “T” to control SS with the rear dial) …and I’m still in Auto-ISO mode, but with a fixed (and non-overridable) SS.

If I need full manual (for astrophotography or whatever), I simply set fixed values on both top dials.

None of these scenarios require anything more than a quick glance down and knob adjustment to engage or disengage an override  - without ever having to hassle with a menu (or even turning the camera on). Instead of constantly adjusting the top dials, I only use them, as needed, to override or partially override the automatic functions when necessary (not all that often).

That’s why I use Auto-ISO.

fujiian wrote:

frostyj75 wrote:

I have the settings at Base ISO - 200, ISO Limit - 6400, and shutter at 1/60th. In bright daylight, the shutter will stay at 1/60th and the ISO will be up over 1000 at times. Isn't the ISO supposed to stay at the base and only raise when the shutter is at the limit?

Are you setting the shutter speed via the dial, or setting it to 'A' alongside ISO (creating 'aperture priority' mode)

A shutter speed (or any setting) set manually on a dial will never be overridden by the camera.

This is probably it.

The OP's story is very strange, in bright daylight SS @ 1/60, and 1000+ ISO??? what aperture was selected?????? with an ND filter??? Something is not right.

It is almost impossible that SS will stay at 1/60 in bright daylight, and having to bump ISO over 1000, even with a very small aperture, unless the SS is manually set at 1/60...

frostyj75 wrote:

Am I not understanding how auto ISO is supposed to work? It is very frustrating, thinking that I'm going to get a certain SS and then notice the ISO has gone up instead of the shutter.

If the shutter speed went up, it would have opposite the desired effect.

If you need more exposure/brightness either the aperture needs to be wider, the ISO has to go up, or the shutter speed has to go down, if you have a minimum shutter speed in place, the camera will reduce the shutter speed until it hits that limit and then, and only then, will it raise the ISO. If your camera raised the ISO, it did so because it had no other choice - either there wasn’t enough light or your chosen aperture was too small for base ISO.

I end up going back to manual ISO, I'm just wondering if there is something I am missing in the equation.

Thanks!

Jeff

Rod McD wrote:

Hi,

I'm going to be controversial and ask 'why switch to auto-ISO?' It doesn't seem to me to offer any significant benefits. It introduces more complexity than setting ISO myself and occasional hidden pitfalls for the unwary. Despite many threads on the subject, I still don't know why anyone bothers.

Absolutely disagree. After wider implementation of autoISO minSS feature among camera manufacturers, I don't understand why someone even bother with manual ISO changes. Of course there are some exception - working with flash and you will set lowest ISO on tripod 😉.

There are hidden pitfalls only for those who are lazy to learn even simple logic behind this setting.

EDIT: in some way is controversial my statement, not yours. I made a poll in our local photography facebook group (2000+ members) regarding using autoISO feature. The results was app. 40% use it, 60% change ISO manually. When I asked several times and in detail "WHY?". The most common answer was, that someone teach them this way and they are used it. I got absolutely no racional reason why to use manual ISO instead of autoISO.

The Fuji gods put a thumping great knob on the top left hand end of my camera to control ISO in a system where their market purports to actually like analogue controls. It's got numbers on it. When the light is bright, I turn it to low numbers. When the light is low (or I specifically want faster SS's) I turn it to higher numbers. It's easy. The light never changes so fast that I need it automated. I knowwhat my camera is set to and I don't get any strange outcomes around the set-up parameters, DR management or electronic flash usage. It's kind of fail-safe - it works beautifully!

Cheers, Rod

frostyj75 wrote:

Hello all, I have been using auto ISO here and there to see what all the fuss is about. I have been really pleased with it and generally top the ISO out at 6400. I have found that it appears to raise the ISO before it raises the shutter speed. When I have my 23mm on, I have the settings at Base ISO - 200, ISO Limit - 6400, and shutter at 1/60th. In bright daylight, the shutter will stay at 1/60th and the ISO will be up over 1000 at times. Isn't the ISO supposed to stay at the base and only raise when the shutter is at the limit?

Am I not understanding how auto ISO is supposed to work? It is very frustrating, thinking that I'm going to get a certain SS and then notice the ISO has gone up instead of the shutter. I end up going back to manual ISO, I'm just wondering if there is something I am missing in the equation.

Thanks!

Jeff

My X100V shows the same behaviour. In bright daylight with correct metering - mostly pattern - it raises the ISO to values up to 1000 or even higher, sometimes with a higher Aperture up to 6400. I've set the min. shutter speed to 1/80.

I come from a Ricoh GR III that most of the times will select an ISO of 100 or 200 in comparable situations.

I take pictures in Aperture Priority, the ISO is set to Auto, DR to Auto and I control the shutter speed as part of the Auto Iso setting.

I've read the replies of other users, too. The high ISO value isn't just shown while shooting, it is in the exif data of the photos.

Just one example. Look at the sky, it wasn't the brightest sky ever, but sunny. The Aperture was very narrow, like F11, but nonetheless, the Ricoh did chose much smaller ISO values on a rainy day.

Berlin, Potsdamer Platz Fuji X100V.  SS 1/80, F11, ISO 1250!

This is just a few meters away, taken with a Ricoh, it wasn't nearly as sunny. I've used a high contrast bw preset, that could be misleading:

Ricoh GR III, shutter speed 1/200, F9, Iso 200

DirkPeh wrote:

frostyj75 wrote:

Hello all, I have been using auto ISO here and there to see what all the fuss is about. I have been really pleased with it and generally top the ISO out at 6400. I have found that it appears to raise the ISO before it raises the shutter speed. When I have my 23mm on, I have the settings at Base ISO - 200, ISO Limit - 6400, and shutter at 1/60th. In bright daylight, the shutter will stay at 1/60th and the ISO will be up over 1000 at times. Isn't the ISO supposed to stay at the base and only raise when the shutter is at the limit?

Am I not understanding how auto ISO is supposed to work? It is very frustrating, thinking that I'm going to get a certain SS and then notice the ISO has gone up instead of the shutter. I end up going back to manual ISO, I'm just wondering if there is something I am missing in the equation.

Thanks!

Jeff

My X100V shows the same behaviour. In bright daylight with correct metering - mostly pattern - it raises the ISO to values up to 1000 or even higher, sometimes with a higher Aperture up to 6400. I've set the min. shutter speed to 1/80.

Can you show an example of this with the exif intact? The only time the ISO should be above base is if the shutter speed has bottomed out or your DR mode requires ISO 320 or 640 to function.

I come from a Ricoh GR III that most of the times will select an ISO of 100 or 200 in comparable situations.

I take pictures in Aperture Priority, the ISO is set to Auto, DR to Auto and I control the shutter speed as part of the Auto Iso setting.

I've read the replies of other users, too. The high ISO value isn't just shown while shooting, it is in the exif data of the photos.

Just one example. Look at the sky, it wasn't the brightest sky ever, but sunny. The Aperture was very narrow, like F11, but nonetheless, the Ricoh did chose much smaller ISO values on a rainy day.

Berlin, Potsdamer Platz Fuji X100V. SS 1/80, F11, ISO 1250!

This is just a few meters away, taken with a Ricoh, it wasn't nearly as sunny. I've used a high contrast bw preset, that could be misleading:

Ricoh GR III, shutter speed 1/200, F9, Iso 200

Erik Baumgartner wrote:

DirkPeh wrote:

frostyj75 wrote:

Hello all, I have been using auto ISO here and there to see what all the fuss is about. I have been really pleased with it and generally top the ISO out at 6400. I have found that it appears to raise the ISO before it raises the shutter speed. When I have my 23mm on, I have the settings at Base ISO - 200, ISO Limit - 6400, and shutter at 1/60th. In bright daylight, the shutter will stay at 1/60th and the ISO will be up over 1000 at times. Isn't the ISO supposed to stay at the base and only raise when the shutter is at the limit?

Am I not understanding how auto ISO is supposed to work? It is very frustrating, thinking that I'm going to get a certain SS and then notice the ISO has gone up instead of the shutter. I end up going back to manual ISO, I'm just wondering if there is something I am missing in the equation.

Thanks!

Jeff

My X100V shows the same behaviour. In bright daylight with correct metering - mostly pattern - it raises the ISO to values up to 1000 or even higher, sometimes with a higher Aperture up to 6400. I've set the min. shutter speed to 1/80.

Can you show an example of this with the exif intact? The only time the ISO should be above base is if the shutter speed has bottomed out or your DR mode requires ISO 320 or 640 to function.

I come from a Ricoh GR III that most of the times will select an ISO of 100 or 200 in comparable situations.

I take pictures in Aperture Priority, the ISO is set to Auto, DR to Auto and I control the shutter speed as part of the Auto Iso setting.

I've read the replies of other users, too. The high ISO value isn't just shown while shooting, it is in the exif data of the photos.

Just one example. Look at the sky, it wasn't the brightest sky ever, but sunny. The Aperture was very narrow, like F11, but nonetheless, the Ricoh did chose much smaller ISO values on a rainy day.

Berlin, Potsdamer Platz Fuji X100V. SS 1/80, F11, ISO 1250!

This is just a few meters away, taken with a Ricoh, it wasn't nearly as sunny. I've used a high contrast bw preset, that could be misleading:

Ricoh GR III, shutter speed 1/200, F9, Iso 200

I've edited my post and added the pictures. The exif is there. The Auto-Iso setting is. IS0 160 up to 6400, the SS is 1/80. The settings on the Ricoh are identical. The DR was set to 100 on the Fuji. I only have the Fuji since a week, so I can't rule out that I make a mistake in the settings, but I don't know what should cause this behaviour.

DirkPeh wrote:

Erik Baumgartner wrote:

DirkPeh wrote:

frostyj75 wrote:

Hello all, I have been using auto ISO here and there to see what all the fuss is about. I have been really pleased with it and generally top the ISO out at 6400. I have found that it appears to raise the ISO before it raises the shutter speed. When I have my 23mm on, I have the settings at Base ISO - 200, ISO Limit - 6400, and shutter at 1/60th. In bright daylight, the shutter will stay at 1/60th and the ISO will be up over 1000 at times. Isn't the ISO supposed to stay at the base and only raise when the shutter is at the limit?

Am I not understanding how auto ISO is supposed to work? It is very frustrating, thinking that I'm going to get a certain SS and then notice the ISO has gone up instead of the shutter. I end up going back to manual ISO, I'm just wondering if there is something I am missing in the equation.

Thanks!

Jeff

My X100V shows the same behaviour. In bright daylight with correct metering - mostly pattern - it raises the ISO to values up to 1000 or even higher, sometimes with a higher Aperture up to 6400. I've set the min. shutter speed to 1/80.

Can you show an example of this with the exif intact? The only time the ISO should be above base is if the shutter speed has bottomed out or your DR mode requires ISO 320 or 640 to function.

I come from a Ricoh GR III that most of the times will select an ISO of 100 or 200 in comparable situations.

I take pictures in Aperture Priority, the ISO is set to Auto, DR to Auto and I control the shutter speed as part of the Auto Iso setting.

I've read the replies of other users, too. The high ISO value isn't just shown while shooting, it is in the exif data of the photos.

Just one example. Look at the sky, it wasn't the brightest sky ever, but sunny. The Aperture was very narrow, like F11, but nonetheless, the Ricoh did chose much smaller ISO values on a rainy day.

Berlin, Potsdamer Platz Fuji X100V. SS 1/80, F11, ISO 1250!

This is just a few meters away, taken with a Ricoh, it wasn't nearly as sunny. I've used a high contrast bw preset, that could be misleading:

Ricoh GR III, shutter speed 1/200, F9, Iso 200

I've edited my post and added the pictures. The exif is there. The Auto-Iso setting is. IS0 160 up to 6400, the SS is 1/80. The settings on the Ricoh are identical. The DR was set to 100 on the Fuji. I only have the Fuji since a week, so I can't rule out that I make a mistake in the settings, but I don't know what should cause this behaviour.

The shutter speed is at your minimum setting and the camera raised the ISO exactly as you would expect it to. Did you inadvertently leave the ND filter on?

Yes, I guess so. Call me stupid, but has it such an impact?

DirkPeh wrote:

Yes, I guess so. Call me stupid, but has it such an impact?

Well yeah, 4 full stops in the V.