Downside of using below native ISO ?

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No worries. I suffer from chronic pain, and both it, and the painkillers I take, can make me a bit short tempered.

I am merely saying what I have observed with my cameras.

While most shots are not particularly affected by small reductions in DR, the reduction in noise by effectively doubling the exposure can be significant.

This is not really an ETTR method, as the camera is compensating for this effective doubling of exposure by changes to the amplification by the ADC. This is different from 'fooling' the camera by using an ETTR approach.

The E-30 is quite a noise machine even at ISO 200, and the noise is quite noticeably reduced by shooting at ISO 100 when possible. It also has some other peculiarities, in that the intermediate digital ISOs are noisier than going to the next full stop ISO setting. The full stop settings appear to be done using the ADC.
I am sorry to hear about your health problems :(!
The difference between using pulled ISO vs. native ISO and overexposing is that pulled ISO is automatic, while with manual positive EC, you have more control.
Everyone picks the method that works best for themselves.
 
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I thought it was done to give a longer exposure in a very bright seen if you needed it.
I have used it like that, i.e., to lower the shutter speed when an ND filter is not around.
Nowadays, I rather stay at native ISO, increase the exposure manually (slower shutter speed), and correct in the post if necessary. I think that gives me more control over my image quality.
 
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Or to maximise the sensor's noise performance (so long as you don't clip highlights).
You can maximize the sensor's performance more precisely by staying at native ISO and manually adjusting exposure for sensor saturation (i.e., no clipping of relevant highlights). It is more trouble, though, but I like controlling manually when and which highlights are being clipped.
 
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I thought it was done to give a longer exposure in a very bright seen if you needed it.
Or to allow very wide apertures in strong light.
Or to maximise the sensor's noise performance (so long as you don't clip highlights).
All of these. But there is no "below native ISO" as it relates to noise. It exists to move the other exposure variables. It appears to be a JPEG-centric feature.

High key scenes would be another scenario where clipped highlights is the aesthetic.
 
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RAH

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ISO is a JPEG-centric feature in general.
I don't know what you mean by this. Even though RAW images are much more fixable, exposure-wise, than jpgs, they still have a limit and need to be in the ballpark with the exposure. Isn't ISO the 3rd leg of the exposure triad (aperture, shutter speed, ISO)? Not arguing, just asking. :)
 
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I don't know what you mean by this. Even though RAW images are much more fixable, exposure-wise, than jpgs, they still have a limit and need to be in the ballpark with the exposure. Isn't ISO the 3rd leg of the exposure triad (aperture, shutter speed, ISO)? Not arguing, just asking. :)
Details about ISO, its alleged part in the exposure triad/triangle, and why it is JPG/TIFF centric:
The Unbearable Lightness of Mystic "Exposure" Triangle
 

PakkyT

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I don't know what you mean by this. Even though RAW images are much more fixable, exposure-wise, than jpgs, they still have a limit and need to be in the ballpark with the exposure. Isn't ISO the 3rd leg of the exposure triad (aperture, shutter speed, ISO)? Not arguing, just asking. :)
Simply put and strictly speaking, the ISO standard for brightness/lightness of an image only applies to the final output of the image such as JPG, TIFF, etc. (and might even only apply to sRGB images). How one gets to the final output is not part of the ISO standard. So in the raw realm the camera manufacturer can do anything they want to create the exposure. The ISO settings, while practically may effect how the camera takes the exposure, is more of an output control telling the camera that when you are done and produce your JPG, that final output should give some sort of expected brightness per the ISO standard.

Olympus and Panasonic camera have taken a more old fashioned route to ISO in that they apply a tonal curve to the exposure and then use simple amplification of the sensor data to output "ISO" brightnesses. Other manufacturers, especially recently, have gone with other methods of brightening an image with things like different tonal curves and playing with using more or less highlight information to create brighter images without actually amplifying the sensor data, or much less amplification, so they can output a higher "ISO" image even if the image was taken with the same base amplification of the sensor data. That is what you have some of these camera now that people refer to as "ISO invariant" where the ISO settings might determine the output brightness but the camera still uses the "base ISO" amplification for each of those ISO settings. Olympus takes advantage of this with the "low" ISO setting where picking ISO 100 or ISO 200 does nothing more than change the shutter speed one stop then auto corrects the resulting exposure back one stop to generate the proper brightness of the image even though both were actually taken with the same sensor amplification.
 

RAH

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Details about ISO, its alleged part in the exposure triad/triangle, and why it is JPG/TIFF centric:
The Unbearable Lightness of Mystic "Exposure" Triangle
I read this article (skimmed some, but I got the idea, I think). But
I guess I'm not understanding this very well. Using these 3 key points from the article

1)“Noise and harm” do not come directly from raising ISO, but from lowering the exposure. That's the justification for setting the hottest exposure you can afford

2) When you raise ISO before setting the exposure, you may limit the exposure. You don't want to do that – for each stop of exposure decrease, the image becomes half a stop "noisier".

3) If you are shooting raw, set the ISO at the base value (minimum ISO option for a given camera, not an extended, or "Lo" one), and set exposure according to your photographic goals, raising it to the limit (constraints: DoF, aberrations / resolution / diffraction, blur, clipping of highlights that are important to the composition of the shot). This will lower the noise and raise the quality of the shot.


would mean that for every shot you take, you should set the ISO to base, then set your aperture and shutter speed, using that (very low) ISO. So, um, what the hell? For many shots, I'd get really slow shutter speeds and/or a wide-open aperture. So what exactly am I supposed to do at that point to get a faster shutter speed?

Assuming the lens is wide open, I'd have to raise the ISO, wouldn't I?

So is he saying that because I started this whole procedure at base ISO and setting an exposure at that base ISO, I get less noise when I finally raise the ISO and set my exposure to what I really want (fast shutter speed, say) than if I had just set the ISO high right from the beginning?

So the sequence would be:
1) crank the ISO down to the base, set your exposure,

2) boosting the ISO and reset the exposure for that higher ISO (to get the faster shutter speed you want).

Is that what he means? If so, how does the 2nd step differ from just starting off with a high ISO? I mean, that's what it is.

Unless he means that you should shoot everything at base ISO, which he cannot possibly mean, I don't think.
 

PakkyT

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Assuming the lens is wide open, I'd have to raise the ISO, wouldn't I?

So is he saying that because I started this whole procedure at base ISO and setting an exposure at that base ISO, I get less noise when I finally raise the ISO and set my exposure to what I really want (fast shutter speed, say) than if I had just set the ISO high right from the beginning?
I think what the article is implying is simply create as much exposure as you can with shutter and aperture. If you can create the exposure you want with just shutter and aperture at base ISO then you are done. Fire the shutter! However if after you have adjusted S&A to their limits (either physically they can't go any slower/bigger or artistically where you have decided you can not go slower/bigger) and the camera meter is still showing way under exposed, then finally increase your ISO to get to the exposure you want. You shouldn't have to re-adjust the shutter or aperture (as you stated in your sequence step 2; no "reset" should be needed).

On that page it is a little confusing 'cause he says use the base ISO and set S&A but doesn't really state that THEN you raise the ISO when you are done. I don't think the page means to imply you always shoot at base ISO.

If you start with a high ISO to begin with, you might be setting it higher than it needs to be and so the camera will adjust "darker" whatever it is allowed to adjust to lower the light to the sensor to compensate. So you would be artificially increasing the lightness of your image ISO starting with an ISO set too high, when you could have gone the same lightness with a larger aperture or slower shutter coupled with lower ISO which in theory should give a cleaner image.
 
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I read this article (skimmed some, but I got the idea, I think). But
I guess I'm not understanding this very well. Using these 3 key points from the article

1)“Noise and harm” do not come directly from raising ISO, but from lowering the exposure. That's the justification for setting the hottest exposure you can afford

2) When you raise ISO before setting the exposure, you may limit the exposure. You don't want to do that – for each stop of exposure decrease, the image becomes half a stop "noisier".

3) If you are shooting raw, set the ISO at the base value (minimum ISO option for a given camera, not an extended, or "Lo" one), and set exposure according to your photographic goals, raising it to the limit (constraints: DoF, aberrations / resolution / diffraction, blur, clipping of highlights that are important to the composition of the shot). This will lower the noise and raise the quality of the shot.


would mean that for every shot you take, you should set the ISO to base, then set your aperture and shutter speed, using that (very low) ISO. So, um, what the hell? For many shots, I'd get really slow shutter speeds and/or a wide-open aperture. So what exactly am I supposed to do at that point to get a faster shutter speed?

Assuming the lens is wide open, I'd have to raise the ISO, wouldn't I?

So is he saying that because I started this whole procedure at base ISO and setting an exposure at that base ISO, I get less noise when I finally raise the ISO and set my exposure to what I really want (fast shutter speed, say) than if I had just set the ISO high right from the beginning?

So the sequence would be:
1) crank the ISO down to the base, set your exposure,

2) boosting the ISO and reset the exposure for that higher ISO (to get the faster shutter speed you want).

Is that what he means? If so, how does the 2nd step differ from just starting off with a high ISO? I mean, that's what it is.

Unless he means that you should shoot everything at base ISO, which he cannot possibly mean, I don't think.
What PakkyT said.

You could follow these steps in order to minimize noise and maximize DR:
- Set base/native ISO
- Set aperture that gives you the desired DoF.
- Set slowest shutter speed that does not clip relevant highlights and is not below the necessary minimum (minimum is defined by the situation, e.g., handheld vs. tripod, still vs. moving subject).
- Increase the ISO if necessary.

What you may want to avoid is to use higher shutter speed & ISO than necessary as it increases noise and decreases DR.
 
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What PakkyT said.

You could follow these steps in order to minimize noise and maximize DR:
- Set base/native ISO
- Set aperture that gives you the desired DoF.
- Set slowest shutter speed that does not clip relevant highlights and is not below the necessary minimum (minimum is defined by the situation, e.g., handheld vs. tripod, still vs. moving subject).
- Increase the ISO if necessary.

What you may want to avoid is to use higher shutter speed & ISO than necessary as it increases noise and decreases DR.
All too complicated, and too slow.

I am very used to looking at the scene, and can 1) set the ISO to a ballpark figure, 2) set aperture to what I need to achieve, and 3) shutter speed will 'follow' along where I want it to be.

Using this method, I'm prepared for what might arise. Using that alternate method, I may as well leave the camera at home ...

For the first 10 years I took photographs, I didn't have a light meter, and ASA (ISO) wasn't easily changeable. You had to be able to judge the light, and set your camera accordingly.

Nowadays, the internet is chock full of people who have some wonderful new way to do things that usually involves (metaphorically) standing on one's head and chanting some secret mantra.
 
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All too complicated, and too slow.

I am very used to looking at the scene, and can 1) set the ISO to a ballpark figure, 2) set aperture to what I need to achieve, and 3) shutter speed will 'follow' along where I want it to be.

Using this method, I'm prepared for what might arise. Using that alternate method, I may as well leave the camera at home ...

For the first 10 years I took photographs, I didn't have a light meter, and ASA (ISO) wasn't easily changeable. You had to be able to judge the light, and set your camera accordingly.

Nowadays, the internet is chock full of people who have some wonderful new way to do things that usually involve (metaphorically) standing on one's head and chanting some secret mantra.
You are right that in many cases, it is just too complicated and too slow. Everybody should shoot the way it works for them. If it is not fun, one should skip it.
 
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You are right that in many cases, it is just too complicated and too slow. Everybody should shoot the way it works for them. If it is not fun, one should skip it.
While Bryan Peterson "Understanding Exposure" might not be precisely technically correct, his methodology works. It also introduces beginners to the basic photographic variables without terrifying them ...

If one adds to Peterson that one should always try to maximise exposure by opening aperture and slowing shutter speed, all is good. Using the minimum appropriate ISO is both sensible and (relatively) self-evident.
 

RAH

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I think what the article is implying is simply create as much exposure as you can with shutter and aperture. If you can create the exposure you want with just shutter and aperture at base ISO then you are done. Fire the shutter! However if after you have adjusted S&A to their limits (either physically they can't go any slower/bigger or artistically where you have decided you can not go slower/bigger) and the camera meter is still showing way under exposed, then finally increase your ISO to get to the exposure you want. You shouldn't have to re-adjust the shutter or aperture (as you stated in your sequence step 2; no "reset" should be needed).

On that page it is a little confusing 'cause he says use the base ISO and set S&A but doesn't really state that THEN you raise the ISO when you are done. I don't think the page means to imply you always shoot at base ISO.
OK, I get what you are saying. And you're right, he never says to increase the ISO so you're left wondering how the hell you can do anything. :)

As @John King says, this is much too slow to use with normal shooting, IMHO. It wouldn't fit at all with the way I usually shoot (again, similar to @John King it seems) - using Aperture priority and presetting the ISO to what I think is necessary for the current conditions, and then shooting away. However, I DO think it is good to know, and if you are shooting say table-top products or non-moving macro stuff, then it would be a good thing to employ.

While I was reading the article I started to think, "Is this guy a relative of Tony Northrup!?!" It is a bit mantra-like! ;)
 
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PakkyT

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As @John King says, this is much too slow to use with normal shooting, IMHO. It wouldn't fit at all with the way I usually shoot (again, similar to @John King it seems) - using Aperture priority and presetting the ISO to what I think is necessary for the current conditions, and then shooting away.
Ya that page is just yet another shooting for ETTR type article and as always while the concept of ETTR is useful in certain situations, for most of us, most of time, for most of what we shoot, the gains from employing this method are minimal at best and not worth the time and effort (both in setting up the shot and in post processing work).

Heck, I don't even preset my ISO. I use Auto-ISO usually and just set the limits on it for what I am comfortable with. In my experience Olympus has already programmed the cameras to use the lowest ISO setting for as long as it can and only raising the ISO as a last resort. So if my camera can use ISO 200, then it will as the first choice. So the camera in a sense already does ETTR when using Auto-ISO since it tries to use the lowest ISO.

My shooting is almost exclusively hand held. Where auto-iso might use higher ISO than needed is when using a tripod. I believe the way Oly camera's handle setting is if, assuming you are shooting aperture priority, the camera will try to use the lowest ISO and then increase shutter time. However I think it then stops reducing shutter time when it gets to what Olympus defines as the minimum shutter speed for hand holding the focal length lens being used. It will then start increasing ISO and only going back to lengthening shutter if it runs out of ISO room. So in that case it is best to pick your ISO and then allow the shutter speed to go as slow as needed since you are on a tripod.

As you said, all great stuff to read and understand, but most of the time more academic than practical in real life usage.
 

RAH

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Heck, I don't even preset my ISO. I use Auto-ISO usually and just set the limits on it for what I am comfortable with. In my experience Olympus has already programmed the cameras to use the lowest ISO setting for as long as it can and only raising the ISO as a last resort. So if my camera can use ISO 200, then it will as the first choice. So the camera in a sense already does ETTR when using Auto-ISO since it tries to use the lowest ISO.

My shooting is almost exclusively hand held. Where auto-iso might use higher ISO than needed is when using a tripod. I believe the way Oly camera's handle setting is if, assuming you are shooting aperture priority, the camera will try to use the lowest ISO and then increase shutter time. However I think it then stops reducing shutter time when it gets to what Olympus defines as the minimum shutter speed for hand holding the focal length lens being used. It will then start increasing ISO and only going back to lengthening shutter if it runs out of ISO room. So in that case it is best to pick your ISO and then allow the shutter speed to go as slow as needed since you are on a tripod.
Interesting what you say about Auto-ISO. Maybe I'll give it a try with the limits set. That's essentially what I am kind of doing manually anyway, and it seems that it is handling it the way a person would want it to. Thanks for the tip! :)
 
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