Pls show examples where increasing brightness in post better than increasing ISO.

Started Oct 1, 2013 | Discussions
OP PhilPreston3072 Senior Member • Posts: 2,586
Re: examples where increasing brightness in post is better than increasing ISO.
1

Andre Affleck wrote:

Not to open any sore wounds, but it is interesting that the other poster still arrived at the correct settings to maintain highlights, even though he understood it as reducing exposure. Just sayin'

You do realise that the poster applied highlight compression/recovery to the ISO100 to bring the highlights back down.  If he simply just pushed the ISO100 6 stops the highlights would be blown too.  He had already blown out the highlights at ISO6400 so there was nothing there to recover there.

If the poster really wanted to recover the highlights at ISO6400 then he should have preserved them in the first place.  Either that, or start with a lower ISO that doesn't blow the highlights at the same shutter and aperture.

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Simon Garrett Veteran Member • Posts: 6,228
Re: Examples

rubank wrote:

bobn2 wrote:

rubank wrote:

bobn2 wrote:

The point about knowing the science is that it lets you take out of the loop a lot of the 'extensive practice'.

Extensive practice has a lot of other benefits. You need 10 000 hours of practice (whatever you engage in) to get proficient. Try it.

That's afigure plucked out of the air with no evidence.

Actually not
http://www.wisdomgroup.com/blog/10000-hours-of-practice/

That article may be a bit qurky, but there is other evidence that points to a number of areas of human endeavour where it appears that people require about 10,000 of study and practice (note: both) to become "experts", by whatever is the standard for that field of endeavour.

This is neither coincidental nor arbitrary: it represents around 5 years full-time effort, which is about the practical time available to acquire a skill.  I mean: in most professions, one can't afford to have people spending much more than that learning before they start contributing back from that learning, hence many professions or whatever average out about there.

The point is that science provides direction much faster than trial and error.

Agreed, but in the case of practical skills such as photography, it helps to have both scientific knowledge and practical experience in applying that knowledge, surely?

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Simon

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EinsteinsGhost
EinsteinsGhost Forum Pro • Posts: 11,977
Re: Pls show examples where increasing brightness in post better than increasing ISO.

bobn2 wrote:

EinsteinsGhost wrote:

Iliah Borg wrote:

People using the ISO first technique will vary rarely set the maximum exposure

Not true, one starts raising ISO when they are already aperture and shutter limited.

Bob says - "people using ISO first technique".

Bob and his ideas on ISO first versus "Auto ISO rules" aside, people start raising their ISO as the last resort, if they have exhausted their other options and especially those who are aware of the compromises with every aspect: aperture, shutter speed AND ISO setting.

Take a look at the sample above. Neither has a good photographic value, and only exists to demonstrate that higher ISO compromises dynamic range. But, if you were to take the same shot, there is a good chance you could explore additional options including lowering the shutter speed perhaps even down to 1/4s and use ISO 800.

The obvious question would be... if you prefer Auto ISO instead, what would be the camera's choice? ISO 100?

The ISO control really doesn't do much except a fine optimisation. It's the exposure that matters.

What fine optimization?

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EinsteinsGhost
EinsteinsGhost Forum Pro • Posts: 11,977
Re: Pls show examples where increasing brightness in post better than increasing ISO.

bobn2 wrote:

EinsteinsGhost wrote:

bobn2 wrote:

EinsteinsGhost wrote:

bobn2 wrote:

Andre Affleck wrote:

People using the ISO first technique will vary rarely set the maximum exposure

Not true, one starts raising ISO when they are already aperture and shutter limited.

Bob says - "people using ISO first technique".

Ok, then I have to question as to how using the method somehow makes one think of ISO first. Its always the last result, after exposure is maximized, regardless of ones understanding of exposure.

Interesting to do a poll, see whether most photographers set the ISO first or last. My guess is first, because the camera user interface is designed that way.

Where do you believe "Auto ISO" folks will fall?

They set last, but they let the camera do it for them.

Auto ISO is set first, and forgotten. I would wager most photographers using Auto ISO fall into that category.

Auto ISO sets the ISO after the other settings have been set, same as if a photographer set them for himself.

But it is the first thing the photographer who can't do without Auto ISO sets. OTOH, a photographer shooting in manual mode uses manual ISO as the last resort, or may not even bother to move the ISO setting past the base ISO at all.

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rubank Senior Member • Posts: 1,091
You might be right, you might be wrong

Here you have a comparison between Photivo, RawTherapee, CaptureOne, an ISO 400 underexposed shot that has been heavily lifted. All noise reduction and sharpening disabled.
For measure, an ACR conversion of the same scene as a more "normal" exposure at ISO 6400.

As far as I´m concerned the RT colour is off.
RT using "neutral" profile, exp slider +4,95.

ProfHankD
ProfHankD Veteran Member • Posts: 6,529
Re: The meaning of ISO, NEX-7 vs. EOS 7D

wchutt wrote:

ProfHankD wrote:

ISO film speed is a bit of a judgement call for sensors used in digital cameras. Basically, the notion of ISO change is implemented by two things:

  • Change of the exposure settings (aperture and shutter speed)
  • Change of the sensor gain

It is physically impossible to increase or decrease the sensor gain.

All sensors operate at a single gain value. Any change in gain (electronic or digital) occurs after the shutter closes.

Yes, gain is applied after the integration period ends (with or without a shutter); I wasn't referring to something like adjusting the quantum efficiency, which is impractical if not impossible. The sensor gain is the gain (amplification) of the analog sensor outputs as they go into the ADCs.

In principle, there should be no difference between increasing brightness (not exposure) by increasing (ISO) using electronic amplification or digital multiplication during post-processing. However the actual results will be highly dependent on the specific camera being used. Besides the convenience of viewing results immediately, the primary reason to use in-camera gain is to get the most out the analog-to-digital converter. Some cameras have ADCs that require no electronic gain to accommodate the ADC technology. The Nikon D7000 and Phase One digital backs are just two examples.

That's what I believe this thread is about. The "ISO-less" sensors would then be the ones where the analog amplification going into the ADCs is essentially a constant.  Then again, the raw files do have different values for different ISOs given the same exposure settings, so something is causing that. In addition, Sony has said some things in the past about dynamically adjusting analog values on sensor to reduce noise -- perhaps compensating for differences between ADCs by incorporating some type of reference level check?

That brings up the question of why postprocessing applying the same digital gain (tone mapping) that is done in-camera would do better than the presumably well-tuned implementation in the camera.  It could just be it isn't so well tuned in some cameras.

I've decided to have my students do a little test using CHDK to compare high camera ISO to low ISO + digital gain on the raw. With CHDK, this can be done using the standard conversion to JPEG in the camera, removing any potential bias in tone mapping.  We'll see what they find....

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EinsteinsGhost
EinsteinsGhost Forum Pro • Posts: 11,977
Free Lunch?
1

Simon Garrett wrote:

rubank wrote:

bobn2 wrote:

rubank wrote:

bobn2 wrote:

The point about knowing the science is that it lets you take out of the loop a lot of the 'extensive practice'.

Extensive practice has a lot of other benefits. You need 10 000 hours of practice (whatever you engage in) to get proficient. Try it.

That's afigure plucked out of the air with no evidence.

Actually not
http://www.wisdomgroup.com/blog/10000-hours-of-practice/

That article may be a bit qurky, but there is other evidence that points to a number of areas of human endeavour where it appears that people require about 10,000 of study and practice (note: both) to become "experts", by whatever is the standard for that field of endeavour.

This is neither coincidental nor arbitrary: it represents around 5 years full-time effort, which is about the practical time available to acquire a skill. I mean: in most professions, one can't afford to have people spending much more than that learning before they start contributing back from that learning, hence many professions or whatever average out about there.

The point is that science provides direction much faster than trial and error.

Agreed, but in the case of practical skills such as photography, it helps to have both scientific knowledge and practical experience in applying that knowledge, surely?

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Jack Hogan Veteran Member • Posts: 6,982
Re: You might be right, you might be wrong

rubank wrote:

Here you have a comparison between Photivo, RawTherapee, CaptureOne, an ISO 400 underexposed shot that has been heavily lifted. All noise reduction and sharpening disabled.
For measure, an ACR conversion of the same scene as a more "normal" exposure at ISO 6400.

As far as I´m concerned the RT colour is off.
RT using "neutral" profile, exp slider +4,95.

Ok, good example. There is enough tonal difference between the four to show that each renders color slightly differently.  The RT 'Neutral' image is normally the least processed - some call it the most 'accurate' - and thus also normally the least pleasing.  Assuming you don't have any out of gamut colors there, and you white balanced each converter by sampling a neutral gray object in the scene, I would tend to trust RT most.

On the other hand the point here was to show the ISO400 and ISO6400* Raw images rendered side by side by the same converter. If I had to choose one, I would choose RT for the reasons above.

Jack

* You know that ISO6400 on a D800 is really ISO1600 pushed 2 stops digitally in-camera before writing data to the Raw file, right? So with this example you'd really only be showing the effects of a 2 stop push (from 400 to 1600).

rubank Senior Member • Posts: 1,091
Re: You might be right, you might be wrong

Jack Hogan wrote:

rubank wrote:

Here you have a comparison between Photivo, RawTherapee, CaptureOne, an ISO 400 underexposed shot that has been heavily lifted. All noise reduction and sharpening disabled.
For measure, an ACR conversion of the same scene as a more "normal" exposure at ISO 6400.

As far as I´m concerned the RT colour is off.
RT using "neutral" profile, exp slider +4,95.

Ok, good example. There is enough tonal difference between the four to show that each renders color slightly differently.

Yes, but the RT conversion sticks out; the others are in the same ballpark (on my monitor, maybe its bad...)

The RT 'Neutral' image is normally the least processed - some call it the most 'accurate' - and thus also normally the least pleasing. Assuming you don't have any out of gamut colors there, and you white balanced each converter by sampling a neutral gray object in the scene, I would tend to trust RT most.

On the other hand the point here was to show the ISO400 and ISO6400* Raw images rendered side by side by the same converter. If I had to choose one, I would choose RT for the reasons above.

Jack

* You know that ISO6400 on a D800 is really ISO1600 pushed 2 stops digitally in-camera before writing data to the Raw file, right? So with this example you'd really only be showing the effects of a 2 stop push (from 400 to 1600).

Of course I do. But the inclusion of the ACR high ISO cenversion was not meant to be a comment on any "ISO-less" debate, but to give a point of reference to colour shifts when doing heavy shadow lifting - which was the topic of this conversation.

While you trust RT I trust my eyes. After all, I know what the plastic containers look like...

For your amusement, here´s another comparison:

from left to right:

ACR using RT:s colour profile, ACR using Adobe Standard profile, RT using its own profile.
ISO 6400. "Exposure" and shadow adjustments were made to somewhat match the output brightness. WB from the same spot.

None of these is good, but RT is not the best among the 3.

ultimitsu
ultimitsu Veteran Member • Posts: 6,650
Re: examples where increasing brightness in post is better than increasing ISO.

PhilPreston3072 wrote:

ultimitsu wrote:

PhilPreston3072 wrote:

I'm afraid you are still missing the point. If you're testing ISO6400 performance and finding that highlights are clipping then of course you have to reduce exposure.

it is you who is missing the point. it is well arguable that both shots got the right brightness - the sky is black and the walls is lit. the fact that inside the building detail preserved is a bonus. reduce ISO to 100 without any in-computer brightening (which is what you are advocating) would give you detail in the building but no details at all on the walls.

Put it this way, did the poster do all he possibly can to preserve highlights when using high ISO? If he did not then I don't know why he's complaining about lost highlight detail. When it comes to lowlight shooting, highlights are much easier to preserve than deep shadows.

When high iso is chosen by the metering system, it is never about high light preservation, it is about overall brightness of the resulting jpeg having "proper brightness" - which is 18% grey.

What you are saying is that people shouldn't do that, they should save highlight using lower iso and brighten the image in processing - that is exactly what "shoot low iso then brighten in post" is all about. You understand the need, obviously. But you insist on arguing otherwise with this thread merely because other people have said it first. It seems narcissistic to me.

gollywop
gollywop Veteran Member • Posts: 8,284
Re: Examples

rubank wrote:

bobn2 wrote:

rubank wrote:

bobn2 wrote:

rubank wrote:

The simple fact is
that you have to choose: will you sacrifice the highlights or the shadows. With a scene where the DR is beyond what your camera can capture in a single exposure, this choice is of greater importance than what ISO routine you prefer.

Do you want to preserve highlights it is often better to choose underexposure at low ISO, at the cost of shadow colour and noise (esp. banding). If shadows are more important it is often better to choose high ISO, at the cost of highlight rendering.

Heavy shadow lifting commonly leeds to colour shift and banding noise, at least with badly lit scenery where major parts of the image is in deep shadow.
In daylight situations with minor parts of the image in deep shadow, lifting in post is mostly not a problem (unless you have an ISO-full camera).

These are my findings, based on extensive practice and not on science.

The point about knowing the science is that it lets you take out of the loop a lot of the 'extensive practice'.

Extensive practice has a lot of other benefits. You need 10 000 hours of practice (whatever you engage in) to get proficient. Try it.

That's afigure plucked out of the air with no evidence.

Actually not
http://www.wisdomgroup.com/blog/10000-hours-of-practice/

The point is that science provides direction much faster than trial and error.

There is no such contradiction. Most science is based on trial and error.

Well, a lot of engineering is trial and error.  And trial and error has indeed helped science.  But the major breakthroughs that have led to modern science, special and general relativity and quantum mechanics, are hardly trial and error.  These Kuhn-sian revolutions are greatly thought beyond trial.

Likewise, the Bacon-ian notion of the hypothetico-deductive process of science, which is really the heart of scientific progress, is hardly properly described by trial and error.

Beyond that, if you're going to come up with a description of "most science," I think it would have to be that most science is experiments conducted to bear out existing theory.  And most of these experiments do bear out the existing theory.

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Reilly Diefenbach
Reilly Diefenbach Forum Pro • Posts: 13,294
Re: You might be right, you might be wrong

Pushing two stops in LR5 from 1600 to 6400, the 6400 is slightly better.  Slightly finer grain, no color blotching (D800e.)  So yeah, I'll go with the higher ISO up until the spike climbs the wall, thanks anyway, gentlemen.

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Iliah Borg Forum Pro • Posts: 25,750
Re: Free Lunch?

First, you need to work from originals; second, I do not think the move you made makes sense; third, I like the roof on the upper one less.

Atgard
Atgard Regular Member • Posts: 433
Re: Preferred compromise

bobn2 wrote:

Steen Bay wrote:

Let's say that in low light I really don't want to use a slower shutter speed than 1/60 sec, but maybe that'll require ISO 3200 to get a 'properly exposed' image with the correct/preferred brightness, and then I'll maybe choose 1/30, ISO 1600 as the preferred compromise instead.

Why would you? The extra camera shake will damage your image more than the extra noise, guaranteed.

I think it depends. Unless you're shooting an object moving at a constant speed, you're never exactly sure what shutter speed you need to freeze the action (with people, for example). You should have a general idea, but you can shoot 5 shots at the same shutter speed and 2 might have no motion blur, while 3 do. Someone may move more quickly, or not move very much in that fraction of a second.

Often, I will try to get away with a lower ISO (for less noise) with a slightly slower shutter speed than I think I need, and take several shots, hoping to get one sharp one.

I would rather have 1 sharp shot at ISO 800 and 4 that I throw away due to motion blur, than just 1 sharp shot at ISO 1600.

I think your argument that setting ISO first always "underexposes" is assuming that for every shot, you can know the exact shutter speed you need in advance, and I think in reality it doesn't usually work quite that way. I think there will be times you end up with "extra" or "wasted" shutter speed and other times your subject moves more quickly than normal.

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gollywop
gollywop Veteran Member • Posts: 8,284
Re: The meaning of ISO, NEX-7 vs. EOS 7D

ProfHankD wrote:

wchutt wrote:

ProfHankD wrote:

ISO film speed is a bit of a judgement call for sensors used in digital cameras. Basically, the notion of ISO change is implemented by two things:

  • Change of the exposure settings (aperture and shutter speed)
  • Change of the sensor gain

It is physically impossible to increase or decrease the sensor gain.

All sensors operate at a single gain value. Any change in gain (electronic or digital) occurs after the shutter closes.

Yes, gain is applied after the integration period ends (with or without a shutter); I wasn't referring to something like adjusting the quantum efficiency, which is impractical if not impossible. The sensor gain is the gain (amplification) of the analog sensor outputs as they go into the ADCs.

In principle, there should be no difference between increasing brightness (not exposure) by increasing (ISO) using electronic amplification or digital multiplication during post-processing. However the actual results will be highly dependent on the specific camera being used. Besides the convenience of viewing results immediately, the primary reason to use in-camera gain is to get the most out the analog-to-digital converter. Some cameras have ADCs that require no electronic gain to accommodate the ADC technology. The Nikon D7000 and Phase One digital backs are just two examples.

That's what I believe this thread is about. The "ISO-less" sensors would then be the ones where the analog amplification going into the ADCs is essentially a constant. Then again, the raw files do have different values for different ISOs given the same exposure settings, so something is causing that. In addition, Sony has said some things in the past about dynamically adjusting analog values on sensor to reduce noise -- perhaps compensating for differences between ADCs by incorporating some type of reference level check?

That brings up the question of why postprocessing applying the same digital gain (tone mapping) that is done in-camera would do better than the presumably well-tuned implementation in the camera. It could just be it isn't so well tuned in some cameras.

Because that well-tuned camera processor (1) may or may not be that well-tuned, (2) results in an 8-bit jpeg with either sRGB or Adobe RGB gamut rather than a 16-bit psd (or otherwise) with a choice of a wider gamut, and (3) and has an in-camera ISO applied to it that may have been too high, resulting in undesired clipped highlights that you were unaware of at the time of shooting.

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gollywop
gollywop Veteran Member • Posts: 8,284
Re: Pls show examples where increasing brightness in post better than increasing ISO.

EinsteinsGhost wrote:

bobn2 wrote:

EinsteinsGhost wrote:

bobn2 wrote:

EinsteinsGhost wrote:

bobn2 wrote:

Andre Affleck wrote:

People using the ISO first technique will vary rarely set the maximum exposure

Not true, one starts raising ISO when they are already aperture and shutter limited.

Bob says - "people using ISO first technique".

Ok, then I have to question as to how using the method somehow makes one think of ISO first. Its always the last result, after exposure is maximized, regardless of ones understanding of exposure.

Interesting to do a poll, see whether most photographers set the ISO first or last. My guess is first, because the camera user interface is designed that way.

Where do you believe "Auto ISO" folks will fall?

They set last, but they let the camera do it for them.

Auto ISO is set first, and forgotten. I would wager most photographers using Auto ISO fall into that category.

Auto ISO sets the ISO after the other settings have been set, same as if a photographer set them for himself.

But it is the first thing the photographer who can't do without Auto ISO sets.

You have me really baffled here.  What do you mean? It can't mean he/she sets the ISO value that auto ISO chooses, so it must mean the setting of auto ISO itself, i.e., turning it on in the menu. So do you mean this is the menu item he/she goes to first and turns on before setting exposure parameters?  If so, what does that have to do with Bob's statement above?

OTOH, a photographer shooting in manual mode uses manual ISO as the last resort, or may not even bother to move the ISO setting past the base ISO at all.

And what is the relevance would the word "resort" in this context?  Do you mean manual-mode shooters who don't or can't use auto ISO "resort" to fixed ISO?  Perhaps you might have used "grudgingly puts up with" or "holds his/her nose while applying."

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gollywop
gollywop Veteran Member • Posts: 8,284
Re: Pls show examples where increasing brightness in post better than increasing ISO.

bobn2 wrote:

ultimitsu wrote:

bobn2 wrote:

So, mostly the metering is checking highlights. The easy technique is to set 2 1/2 or a bit more stops of EC and spot meter off the highlights (if your camera lets you use EC in M). On most camera there are a few ISO settings to be working with, and you know those pretty well anyway.

This sounds quite interesting, can you elaborate a bit on how it works? why 2.5 stops?

Your meter should be calibrated to centre when it gets 18% grey as the nominal exposure (10/ISO lux seconds). So, you need to miscalibrate it to regard 100% as nominal. According to ISO, the ratio of highlight to 18% is 78/10 = 7.8 = 2.96 stops (funny what these discussions can do - I see I miscalculated a long time ago, and have been giving my highlights a bit less than I could - dial in 3 stops). So, if the meter reads highlight and thinks it's 18% grey, it will give 3 stops less exposure than it should - so you correct that with EC, or recalibrating the meter (most will not let you recalibrate that far). In practice if you know how much headroom your camera has, you could dial in more than that.

(Just going back through my working, I realise where the extra half a stop came from, ISO leaves 1/2 stop for specular highlights over white - I must have taken it off somewhere along the line - 3 stops is better)

Actually Bob, the 2-1/2 stops may be a good bet much of the time. It really depends on how well the metering spot fits into the brightest highlights. If the spot is fully contained in the brightest highlights, then you can use 2-3/4 to 3 EV. But, if the spot only partially contains the brightest highlights (and some less than brightest), the lowered metering will result in settings that will overexpose the brightest parts. In this case a lower EC, like 2-1/2 or even 2 is desirable.

This can become a problem when the brightest parts of the scene are important but relatively small, as when sunlight is shining through tree leaves. Lots of potential for blowing, but no "brightest" area large enough to meter fully.

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Horshack Veteran Member • Posts: 7,601
An example
1

IMO the two biggest benefits of ISOless shooting are dynamic range and not having to worry about image brightness at the time of shooting. For the latter if you're shooting in conditions that would otherwise require elevated ISO you simply set the ISO to base (or to whatever level is optimal for that sensor) and never worry about setting ISO thereafter.

The example, pushed 5EV in post. Notice how the image on the television is retained by shooting at ISO 100. If I had shot at ISO 3200 the TV image would have been blown out.

Oriignal (ISO 100)

Post-processed

On all the cameras I have there actually is an IQ compromise when shooting at base ISO. For example on my D800 there is more noise and shadow tinting when using ISO 100 pushed to ISO 3200/6400 than when shooting at ISO 800 and pushed to the same output brightness.

Great Bustard Forum Pro • Posts: 42,853
Excellent example!
1

Horshack wrote:

IMO the two biggest benefits of ISOless shooting are dynamic range and not having to worry about image brightness at the time of shooting. For the latter if you're shooting in conditions that would otherwise require elevated ISO you simply set the ISO to base (or to whatever level is optimal for that sensor) and never worry about setting ISO thereafter.

The example, pushed 5EV in post. Notice how the image on the television is retained by shooting at ISO 100. If I had shot at ISO 3200 the TV image would have been blown out.

Oriignal (ISO 100)

Post-processed

Nicely demonstrated!

On all the cameras I have there actually is an IQ compromise when shooting at base ISO. For example on my D800 there is more noise and shadow tinting when using ISO 100 pushed to ISO 3200/6400 than when shooting at ISO 800 and pushed to the same output brightness.

Interesting.  According to sensorgen's figures (derived from DxOMark data), that should not be the case.  That said, I've heard that some (most?) RAW converters may make use of the ISO setting information in the conversion.  For example, an ISO 100 file will be converted differently than an ISO 800 file, based on assumptions about the scene as a function of the selected ISO.  Perhaps someone can confirm or deny this.

gollywop
gollywop Veteran Member • Posts: 8,284
Re: Pls show examples where increasing brightness in post better than increasing ISO.
1

Jeff wrote:

texinwien wrote:

Jeff wrote:

bobn2 wrote:

ultimitsu wrote:

bobn2 wrote:

So, mostly the metering is checking highlights. The easy technique is to set 2 1/2 or a bit more stops of EC and spot meter off the highlights (if your camera lets you use EC in M). On most camera there are a few ISO settings to be working with, and you know those pretty well anyway.

This sounds quite interesting, can you elaborate a bit on how it works? why 2.5 stops?

Your meter should be calibrated to centre when it gets 18% grey as the nominal exposure (10/ISO lux seconds). So, you need to miscalibrate it to regard 100% as nominal. According to ISO, the ratio of highlight to 18% is 78/10 = 7.8 = 2.96 stops (funny what these discussions can do - I see I miscalculated a long time ago, and have been giving my highlights a bit less than I could - dial in 3 stops). So, if the meter reads highlight and thinks it's 18% grey, it will give 3 stops less exposure than it should - so you correct that with EC, or recalibrating the meter (most will not let you recalibrate that far). In practice if you know how much headroom your camera has, you could dial in more than that.

(Just going back through my working, I realise where the extra half a stop came from, ISO leaves 1/2 stop for specular highlights over white - I must have taken it off somewhere along the line - 3 stops is better)

This is more or less what I've learned to do when shooting in challenging light, but with a small twist.

My E-P5 allows me to adjust the level for shadow and highlight 'blinkies', which I've set at jpeg levels 5 and 250, respectively. In A priority, the rear control wheel adjusts aperture, and the front control wheel adjusts EC.

When taking a shot, exposure is set by keeping an eye on the blinkies while adjusting EC, and while monitoring everything else to be sure I'm not totally killing the shadows. EC will generally fall between -0.5 and -2.5, but the critical issue is watch where the highlights and shadows fall on the live histogram and, via the blinkies, on the image.

The resulting jpeg preview may look off (generally too dark) but this procedure will give me a good raw file for subsequent processing in LR. ISO is a tertiary consideration. I generally try to work at base ISO, but will increase ISO as necessary to keep the viewfinder and jpeg previews usable.

Here are some results http://www.flickr.com/photos/jck_photos/sets/72157635431417147/

It becomes second nature pretty quickly.

I started typing a similar reply, took a break, and here you've gone and done the work, yourself!

The live-view 'blinkies' overexposure indicators are a boon to ETTR raw photogs. Add sufficient controls (i.e. Olympus E-M5, E-P5, E-M1) and you have an ETTR dream machine.

I, too, started out in A mode, mostly, but since Anders W convinced me that there was little advantage to A or S over M when using the blinkies method of ETTR, I have switched, and stay in M 99% of the time.

What comes out are images that are usually within a (<1/3) fraction of a stop from optimal ETTR. As much light as possible collected without blowing any important highlights - consistently.

Since the E-M5 (and E-P5) sensor is not 100% ISO-invariant, I do switch between ISO 200, 400 and 800 (rarely 1600). My sincere hope is that the next generation of OM-D models will be truly ISO-invariant, so I can forget that useless (to me) throwback to ancient history and get on with making properly-exposed photographs - one less useless variable to have to keep in mind.

Couldn't agree more. I've been experimenting a bit with the level settings for the blinkies. 5 and 250 may be unnecessarily conservative, but produce good files. 2 and 253

Anders W is probably right (as usual), but I just like how the controls work in A mode. Back wheel A, front wheel EC, and it's totally second nature. Flick the 2x2 control and then ISO is on the front wheel. I am using M mode more often, but A mode just feels more intuitive to me. Admittedly, this is a personal quirk.

Oly could really own this with a few more tweaks of their UI. They're pretty close now.

With the E-M5 and UniWB, I've found no need to adjust the histogram sensitivity at all. I keep it at 0, 255 and find it works splendidly. I believe Anders found the same thing using autoWB. The typical 1/3EV difference between UniWB and autoWB settings was made up by the fact that I adjust EC (or exposure) to "just under" blinkies, while Anders adjusted to "just showing" blinkies.

I tried Anders' method extensively while traveling this past spring, and I have to agree that it works just as well as the UniWB. I came back with 450 shots (not counting WhiBal readings) and absolutely none of them was problematic for exposure as assessed by RawDigger.

That's not to say I didn't have shots that were incorrect, but I was able to determine that situation immediately with the post-shot blinkies and retake as needed.

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gollywop

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