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4dampadac

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Is there any reason why others use manual iso in manual mode instead of auto ?
 
jrtrent said:
David1961 said:
jrtrent said:
  • Bob A L wrote:
Just to modern hi tech photographers maybe. To a lot of us old guys, for 40 years or so I and any of my friends would have called a photo that was too dark underexposed and a photo that was too light overexposed and some of us still do. Things used to be so much simpler.
Click to expand...
Before joining DPR forums I used to think like you until I had it drummed into me what exposure actually is and that ISO is not an exposure control.

Suddenly things became much clearer in terms of the roles aperture, shutter speed and ISO play.

Using incorrect terminology, although yes it is common, does not make it correct and should not be thrust upon newbies to photography.

I just wish that the "old guys" you refer to updated their knowledge on what exposure actually is in reality otherwise they leave themselves wide open to justifiably being corrected, at least for the sake of correctly educating newbies.

I posted the definition of exposure I accept and I see you are still unable to answer my question to you regarding what definition of exposure you accept.

Maybe you don't have one?
Click to expand...
Maybe he didn't define exposure, but I like his definitions of underexposed and overexposed. Below is a way of thinking about exposure that I like. Perhaps you used to like something similar:

"A photograph's exposure determines how light or dark an image will appear when it's been captured by your camera. Believe it or not, this is determined by just three camera settings: aperture, ISO and shutter speed . . ." https://www.cambridgeincolour.com/tutorials/camera-exposure.htm

If my brother asks what exposure I gave that picture I sent him of a gnome our aunt sent decades ago, I can say the exposure was 1/15 second, f/1.8, and ISO 100.
Click to expand...
That is exactly what I thought but I realise now that is totally incorrect now that I accept:

Exposure = amount of light that hits the sensor per unit area.

Clearly only scene illumination, aperture and shutter speed affect the amount of light that hits the sensor and hence exposure.

ISO clearly does not affect exposure but it sets the image lightness after the shutter has closed and no more light can hit the sensor.
 
FingerPainter said:
Why do you care what exact ISO you have? What reason do you have for wanting to control the ISO setting?
Click to expand...
There are several reasons I've taken control of ISO.

When I delegated ISO selection to the camera and its internal meter, it would occasionally select an overly-high ISO that would blow out highlights to such an extent they were unrecoverable. It only happened a few times but that was enough to be annoying. I'm not perfect but, if a photo is going to be ruined by a bad setting choice, I want to be the one responsible. If I'm gonna feel the sting, I might as well own it.

For landscape photography and portraiture, I like to shoot at or within a stop of base ISO, as this corresponds to an exposure allowing me to take advantage of the camera's full dynamic range. Why delegate that choice when I've plenty of time and opportunity to get it, right?

For birds and wildlife, I'm often using shutter speeds that, even with the lens wide open, are not conducive to being at base. I usually shoot with the lowest ISO in the invariant range for the camera. That gives me the greatest flexibility to manipulate the image in post without compromising image quality. I've chosen exposure settings that balance my creative needs for depth of field and freezing of motion with my goal of maximizing exposure for inherently good image quality. If I'm at the low end of the invariant range, I can push an image several stops in post with the knowledge I'm not compromising on IQ.

Of course, I'm typically making global adjustments to image lightness in post of 0.5-stop or less...often 0.3-stop or less. That's another advantage of shooting full manual.

ISO is an indicator of exposure. While there are times when I need exposure settings demanding an ISO of 1000+ to achieve an acceptable image lightness, those times and conditions are not typical. If I'm getting a pleasing result with my exposure settings and an ISO of 400-500, I know I'm capturing enough light to make a quality image...assuming I'm not cropping too much.

And then there's the convenience factor. I shoot full manual (exposure settings, ISO and white balance) for everything. I've mastered one approach I can apply to all situations. For me, that's a lot easier than mastering a different approach to each genre of photography I do.

For sports photography beneath the artificial lights of an indoor venue once I've set shutter speed, f-stop, and white balance, I'm set for the next few hours. I only check those settings for two reasons: to make sure I haven't accidentally changed something, and when I turn my attention to the color surrounding the game, and want a slower shutter speed, or greater depth of field. Otherwise locking in those settings during pregame warmups allows me to focus all my attention on composition and moment.

Finally, it keeps me mentally in the game. When I'm sitting at the base of a tree beneath a fabric hide in the dark waiting for the morning light to arrive and make photography possible, it's really easy to just close my eyes and zone out. Checking the light level every few minutes and adjusting ISO keeps me engaged. Frankly, this is why I started selecting white balance in the field. I shoot raw so, it's totally unnecessary. But it gives me something to do and experiment with while I'm waiting for action. It keeps me in the moment.

Anyway, these are my reasons. They work for me and may work for others. Fortunately, cameras have the flexibility to be setup to match the sensibilities of the individual pressing the buttons.

--
Bill Ferris Photography
Flagstaff, AZ
http://www.billferris.photoshelter.com
 
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Bob A L said:
But you miss the point - I don't shoot raw - have absolutely no need for it. As explained I have absolutely no intention to process any photo I take in my computer, My camera does that. I admit to messing up on occasion, and either have to throw something away or break down and fix it in the computer, but don't need raw to do that. And my exposure (lightness) does change if I take two photos under the same lighting using the same aperture and shutter speed but with different ISO settings unless I fix them in the computer later. As to cameras I use Nikon, Panasonic, Olympus, Sony, and Canon and they all work the same.
Click to expand...
And all are probably ISO invariant to one degree or another. Whether you choose to take advantage of that, is up to you. And if you've got a system for choosing settings that produce photos you like, there's probably no reason to change.

All that said, the fact remains that ISO is not an exposure setting. It does not directly affect the amount of light delivered to the sensor. It is a setting used by the camera after the exposure to manage the lightness with which a JPEG is rendered.
 
BrentSchumer said:
FingerPainter said:
It seems to me to make sense set the control that actually controls what it is you want to control. You set the EC directly, to something other than 0, when you know that you want the image lightness to be different from what it would be with the default metering solution, and you set the EC to 0 when the default solution is what you want.

Why do you care what exact ISO you have? What reason do you have for wanting to control the ISO setting?

An exact ISO, unlike an exact f-number or an exact shutter speed or an exact EC setting, doesn't correspond directly to any visible aspect of a photo.

I'd have thought you'd care about how light or dark the image was, relative to the typical metering solution.
Click to expand...
If I rely on auto-ISO, I have to carefully monitor the shutter speed when out-and-about. E.g. I have the shutter set at 1/150s to capture routine action and then stop and take a picture of a shady statue. If I'm on manual ISO it will be obvious that the image is under-exposed and I can dial back the shutter speed. If I'm on auto-ISO I might forget about my high shutter speed and shoot at a higher ISO, degrading image quality. That's an artificial example, but I find that it's more effort to "police" auto ISO than to quickly manually set the property with a flick of my wrist. a bright rock to a dark bush. In both situations the bird

Even in situations where my manual ISO is off I'm almost always under-exposing (fixable with ISO-invariant sensors) whereas the auto-ISO general over-exposes (tougher to correct). Especially with my compact camera I really want to minimize ISO to maximize quality, and controlling exposure trade-offs with a 1" sensor requires more finesse than the metering mode can handle.
Click to expand...
I guess it depends on everyone's preferred method of taking photos when "out an about" as you mention.

Especially when I am out an about, I much prefer manual mode because it gives me the benefits of both aperture priority and shutter priority simultaneously without wasting time toggling between the two modes and I set ISO to Auto so I don't have to worry about it at all. The camera does a great job in choosing the most appropriate ISO in 99% of the time.

I simply set the widest aperture that I know will give me the DOF I want and the slowest shutter speed that I can comfortably hand hold at to meet my motion blur requirements for the scene without clipping important highlights.

If the image is still too dark I use EC to raise the ISO (preferably) or I can adjust the image lightness in post processing (less preferable).

This method suits me very well because all I really need to concentrate on is setting the aperture and shutter speed to meet my DOF and motion blur requirements without clipping important highlights and without having to toggle between aperture priority or shutter priority modes.
 
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BrentSchumer said:
FingerPainter said:
It seems to me to make sense set the control that actually controls what it is you want to control. You set the EC directly, to something other than 0, when you know that you want the image lightness to be different from what it would be with the default metering solution, and you set the EC to 0 when the default solution is what you want.

Why do you care what exact ISO you have? What reason do you have for wanting to control the ISO setting?
Click to expand...
Click to expand...
You haven't really answered either of these two questions. Instead you gave an unusual reason for why you want to use manual ISO setting in general, without reference to a particular ISO value.
BrentSchumer said:
BrentSchumer said:
An exact ISO, unlike an exact f-number or an exact shutter speed or an exact EC setting, doesn't correspond directly to any visible aspect of a photo.

I'd have thought you'd care about how light or dark the image was, relative to the typical metering solution.
Click to expand...
If I rely on auto-ISO, I have to carefully monitor the shutter speed when out-and-about.
Click to expand...
Why? You are in manual mode. The shutter is at whatever you set it at. If you are likely to forget what you set it at, you should just check what it is. If you can neither remember the shutter speed in Manual mode, nor remember to check what it is when you don't remember what it is, you have a serious memory problem or a technique problem, or both. Effective technique for use of manual mode requires making settings choices deliberately for each new scene. If you are forgetting to do that, you need to work on your shooting discipline.
BrentSchumer said:
E.g. I have the shutter set at 1/150s to capture routine action and then stop and take a picture of a shady statue.
Click to expand...
To me, the fact that I have switched subjects is sufficient indication that I need to think about my aperture and shutter settings. No further mnemonic is needed.
BrentSchumer said:
If I'm on manual ISO it will be obvious that the image is under-exposed and I can dial back the shutter speed. If I'm on auto-ISO I might forget about my high shutter speed and shoot at a higher ISO, degrading image quality. That's an artificial example, but I find that it's more effort to "police" auto ISO than to quickly manually set the property with a flick of my wrist. a bright rock to a dark bush. In both situations the bird

Even in situations where my manual ISO is off I'm almost always under-exposing (fixable with ISO-invariant sensors)
Click to expand...
Not really fixable with either invariant or variant sensors. You cannot fix the fact that your underexposure captured less light and therefore caused unnecessary noisiness. is the dynamic range of your camera so low that blown highlights are always more of a problem than noise?
BrentSchumer said:
whereas the auto-ISO general over-exposes (tougher to correct).
Click to expand...
Only tougher if it blew desired highlight detail. If it didn't, it is actually easier to fix than underexposure.
BrentSchumer said:
Especially with my compact camera I really want to minimize ISO to maximize quality,
Click to expand...
Setting base ISO only maximizes noise performance if there is no highlight headroom at the widest aperture and slowest shutter you are willing to use. Otherwise, for just about every digital stills camera, you will get better noise performance by increasing ISO to just before the point of clipping.
BrentSchumer said:
and controlling exposure trade-offs with a 1" sensor requires more finesse than the metering mode can handle.
Click to expand...
How so?
 
FingerPainter said:
A lot of people believe this to be true of themselves. Based on what I've seen in these fora, only a few are correct. You may be one of the few.
Click to expand...
And based on comments like these I’ve seen in these fora is why I unsubscribe from threads. ::sigh::
 
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Bill Ferris said:
4dampadac said:
Is there any reason why others use manual iso in manual mode instead of auto ?
Click to expand...
I manually select ISO because I make better choices than the camera.
Click to expand...
The camera doesn't make any ISO "choices" per se, in M mode with auto-ISO. It is completely deterministic and based on the exact same meter that tells you what your mean exposure is in full-M mode.

It will give you the exact same ISO that you would get if you changed the ISO manually until the meter shows the exact same bias as you would have set for "EC" with auto-ISO-M.

IOW, you just dial in the EC that is the same as the way you would have the metering biased in full manual, and you get the same RAW and JPEG levels, and ISO. The difference is, if you fail to pay attention, your EC might be +1 when you really wanted -1/3, so you're 1.33 stops off in ISO. In full manual, if you don't pay attention, you can be several stops off in a big change of lighting.

Full manual, IMO, is only a superior method for doing tests, or shooting in known, constant lighting. With variable light, you can bias your ISO just as well with auto-ISO and EC control, in M mode, with less room for disasters when you don't have time to make perfect settings.
 
Pocket Lint said:
4dampadac said:
Is there any reason why others use manual iso in manual mode instead of auto ?
Click to expand...
When your camera meter isn’t exposing the scene how you want it and you are blowing out details in highlights or losing details in shadows... n/t
Click to expand...
Some of the first cameras that offered auto-ISO did so without EC (ISO bias) in M mode, which is really ridiculous, but it generally comes with ISO bias these days, and you can set the same bias as you would by dialing the ISO directly, as long as it is within the EC range of the camera. My last several cameras have plus or minus 5 stops of range; ample for most situations.

There are fewer reasons to need full manual than there were in the past, and almost all of them involve constant lighting or well-controlled flash.
 
BrentSchumer said:
4dampadac said:
Is there any reason why others use manual iso in manual mode instead of auto ?
Click to expand...
Sometimes I want to expose a picture in a different way than my camera's metering would default to, so I pick all three exposure properties. Not every photo is exposed the same way, and my camera can only guess.
Click to expand...
There's no guessing with auto-ISO in M mode. It is deterministic, based on the meter. In any camera that gives "EC" (ISO bias), you can get the exact same results by dialing in the same offset as you would with full manual.

Perhaps you're confusing auto-ISO in M mode with auto-ISO in Av, Tv, or P modes (Canon lingo; sorry if yours is different). They are COMPLETELY different beasts. The camera has no choices in the former, but makes choices in the latter (but many cameras let you set limits and priorities, there, too).
 
David1961 said:
BrentSchumer said:
FingerPainter said:
It seems to me to make sense set the control that actually controls what it is you want to control. You set the EC directly, to something other than 0, when you know that you want the image lightness to be different from what it would be with the default metering solution, and you set the EC to 0 when the default solution is what you want.

Why do you care what exact ISO you have? What reason do you have for wanting to control the ISO setting?

An exact ISO, unlike an exact f-number or an exact shutter speed or an exact EC setting, doesn't correspond directly to any visible aspect of a photo.

I'd have thought you'd care about how light or dark the image was, relative to the typical metering solution.
Click to expand...
If I rely on auto-ISO, I have to carefully monitor the shutter speed when out-and-about. E.g. I have the shutter set at 1/150s to capture routine action and then stop and take a picture of a shady statue. If I'm on manual ISO it will be obvious that the image is under-exposed and I can dial back the shutter speed. If I'm on auto-ISO I might forget about my high shutter speed and shoot at a higher ISO, degrading image quality. That's an artificial example, but I find that it's more effort to "police" auto ISO than to quickly manually set the property with a flick of my wrist. a bright rock to a dark bush. In both situations the bird

Even in situations where my manual ISO is off I'm almost always under-exposing (fixable with ISO-invariant sensors) whereas the auto-ISO general over-exposes (tougher to correct). Especially with my compact camera I really want to minimize ISO to maximize quality, and controlling exposure trade-offs with a 1" sensor requires more finesse than the metering mode can handle.
Click to expand...
I guess it depends on everyone's preferred method of taking photos when "out an about" as you mention.

Especially when I am out an about, I much prefer manual mode because it gives me the benefits of both aperture priority and shutter priority simultaneously without wasting time toggling between the two modes and I set ISO to Auto so I don't have to worry about it at all. The camera does a great job in choosing the most appropriate ISO in 99% of the time.

I simply set the widest aperture that I know will give me the DOF I want and the slowest shutter speed that I can comfortably hand hold at to meet my motion blur requirements for the scene without clipping important highlights.

If the image is still too dark I use EC to raise the ISO (preferably) or I can adjust the image lightness in post processing (less preferable).

This method suits me very well because all I really need to concentrate on is setting the aperture and shutter speed to meet my DOF and motion blur requirements without clipping important highlights and without having to toggle between aperture priority or shutter priority modes.
Click to expand...
It's all personal preference. I also forgot to mention the dual-gain ISO on newer Sony bodies, which makes ISO640 an important threshold.
 
FingerPainter said:
BrentSchumer said:
FingerPainter said:
It seems to me to make sense set the control that actually controls what it is you want to control. You set the EC directly, to something other than 0, when you know that you want the image lightness to be different from what it would be with the default metering solution, and you set the EC to 0 when the default solution is what you want.

Why do you care what exact ISO you have? What reason do you have for wanting to control the ISO setting?
Click to expand...
Click to expand...
You haven't really answered either of these two questions. Instead you gave an unusual reason for why you want to use manual ISO setting in general, without reference to a particular ISO value.
FingerPainter said:
FingerPainter said:
An exact ISO, unlike an exact f-number or an exact shutter speed or an exact EC setting, doesn't correspond directly to any visible aspect of a photo.

I'd have thought you'd care about how light or dark the image was, relative to the typical metering solution.
Click to expand...
If I rely on auto-ISO, I have to carefully monitor the shutter speed when out-and-about.
Click to expand...
Why? You are in manual mode. The shutter is at whatever you set it at. If you are likely to forget what you set it at, you should just check what it is. If you can neither remember the shutter speed in Manual mode, nor remember to check what it is when you don't remember what it is, you have a serious memory problem or a technique problem, or both. Effective technique for use of manual mode requires making settings choices deliberately for each new scene. If you are forgetting to do that, you need to work on your shooting discipline.
FingerPainter said:
E.g. I have the shutter set at 1/150s to capture routine action and then stop and take a picture of a shady statue.
Click to expand...
To me, the fact that I have switched subjects is sufficient indication that I need to think about my aperture and shutter settings. No further mnemonic is needed.
FingerPainter said:
If I'm on manual ISO it will be obvious that the image is under-exposed and I can dial back the shutter speed. If I'm on auto-ISO I might forget about my high shutter speed and shoot at a higher ISO, degrading image quality. That's an artificial example, but I find that it's more effort to "police" auto ISO than to quickly manually set the property with a flick of my wrist. a bright rock to a dark bush. In both situations the bird

Even in situations where my manual ISO is off I'm almost always under-exposing (fixable with ISO-invariant sensors)
Click to expand...
Not really fixable with either invariant or variant sensors. You cannot fix the fact that your underexposure captured less light and therefore caused unnecessary noisiness. is the dynamic range of your camera so low that blown highlights are always more of a problem than noise?
FingerPainter said:
whereas the auto-ISO general over-exposes (tougher to correct).
Click to expand...
Only tougher if it blew desired highlight detail. If it didn't, it is actually easier to fix than underexposure.
FingerPainter said:
Especially with my compact camera I really want to minimize ISO to maximize quality,
Click to expand...
Setting base ISO only maximizes noise performance if there is no highlight headroom at the widest aperture and slowest shutter you are willing to use. Otherwise, for just about every digital stills camera, you will get better noise performance by increasing ISO to just before the point of clipping.
FingerPainter said:
and controlling exposure trade-offs with a 1" sensor requires more finesse than the metering mode can handle.
Click to expand...
How so?
Click to expand...
It's clear from how you word your replies that you're working out some personal issues by being aggressive and condescending on forums. You're not worth replying to and I sincerely hope you redirect your efforts into a better quality of life.
 
John Sheehy said:
Pocket Lint said:
4dampadac said:
Is there any reason why others use manual iso in manual mode instead of auto ?
Click to expand...
When your camera meter isn’t exposing the scene how you want it and you are blowing out details in highlights or losing details in shadows... n/t
Click to expand...
Some of the first cameras that offered auto-ISO did so without EC (ISO bias) in M mode, which is really ridiculous, but it generally comes with ISO bias these days, and you can set the same bias as you would by dialing the ISO directly, as long as it is within the EC range of the camera. My last several cameras have plus or minus 5 stops of range; ample for most situations.

There are fewer reasons to need full manual than there were in the past, and almost all of them involve constant lighting or well-controlled flash.
Click to expand...
 
David1961 said:
It makes no difference if the sensor is dual gain or not.
Click to expand...
If you have to raise shadows further after exposure on a newer Sony A7 it will look better if the image is taken at ISO-640 than ISO-500.

David1961 said:
The a7R III, like many Sony predecessors, has a separate higher conversion gain (HCG) circuit at the pixel. You can think of this circuitry as amplifying the signal at the pixel level more than at lower ISOs, at the cost of higher tones, to protect it from any downstream noise.*** The a7R III, like its predecessor and the a9, switches to this HCG mode at ISO 640, using it for higher ISOs as well. The HCG mode ensures the camera has amplified its signal so much that any remaining noise barely affects it before it's digitized.
Click to expand...
David1961 said:
Below ISO 640 there's some extra noise to, say, shooting ISO 100 and boosting 6 EV in post as opposed to shooting ISO 640 and boosting 3.3 EV.
Click to expand...
 
Pocket Lint said:
John Sheehy said:
Pocket Lint said:
4dampadac said:
Is there any reason why others use manual iso in manual mode instead of auto ?
Click to expand...
When your camera meter isn’t exposing the scene how you want it and you are blowing out details in highlights or losing details in shadows... n/t
Click to expand...
Some of the first cameras that offered auto-ISO did so without EC (ISO bias) in M mode, which is really ridiculous, but it generally comes with ISO bias these days, and you can set the same bias as you would by dialing the ISO directly, as long as it is within the EC range of the camera. My last several cameras have plus or minus 5 stops of range; ample for most situations.

There are fewer reasons to need full manual than there were in the past, and almost all of them involve constant lighting or well-controlled flash.
Click to expand...
Yes John, I think most of us agree with your statement, I myself shoot in M with auto-ISO most of the time out of convenience, and I usually get a good exposure that way. However, there are some instances where it’s just not ideal, and going full manual is the most ideal situation. In fact last evening was one of those situations for me, where I had to set my ISO to 100 and adjust my aperture or shutter speed to get my desired result. I wish digital didn’t blow highlights so fast, I think the next major update to digital should be increasing the highlight ceiling. I don’t care so much about shadows, if I need to expose shadows to get detail I can always take my time and setup tripod or steady the camera somehow to get that lower SS.

Anyway! Why are we talking about all this, OP’s question was short and sweet and simple.
Click to expand...
Well, even this post of yours at the bottom of the thread is still on topic for the OP's question of "Is there any reason why others use manual iso in manual mode instead of auto?" In addition, I think some of us are milling around making small talk while waiting for our host, the OP, to return to the room.
 
David1961 said:
It still doesn't matter. I still prefer to use Auto ISO.
Click to expand...
That's totally fine; it's a personal preference. I'm just noting that exact ISO values do matter quite a bit for some cameras.

I don't believe that your 90D has the same concern.
 
Last edited:
David1961 said:
I still prefer to use Auto ISO on my other 2 cameras as well, so not sure what point you are trying to make.
Click to expand...
On certain popular cameras the exact ISO value matters quite a bit for post-processing. So manually dialing it in instead of relying on metering yields better images.

But this is a thread for arguing, not explaining, I guess.
 
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