How to determine when the midtones are properly exposed using the exposure module?

I have discoverd that you can use the tone equalizer to bring the highlights “back in check” by lowering the nodes on the right side (highlights) and leaving the filmic module as is…

IMHO bracketing is a good tool to capture a high dynamic range scene if the subject allows. What I’m finding with my shooting is 1) certain subjects like moving railway trains just don’t work with it and 2) the still lifes I’ve recently taken up may have significant shadow components but i usually end up just pushing them down into dark oblivion.

I’ve gradually shifted my thinking about exposure at capture from the midtones to the highlights. I now work to anchor the exposure to preserve highlights and work the rest of the image in post. That isn’t usually ETTR, as I currently lean heavily on my camera’s Highlight-Weighted Matrix metering, which is JPEG-based. With the Nikon Z 6, I’ve found there’s enough dynamic range to let me get away with that in most cases; with the old D7000, not so much. A lazy approach, no doubt, but I grew rather weary of the ‘stupid pet tricks’ required to do balls-to-the-wall ETTR…

The Z 6 also has a two-exposure HDR mode, lets you capture two successive images and it makes the merged JPEG for you. Decent performance, and it’ll let you retain the two captures as NEFs to be played with in post with HDRMerge or the like. The two captures are very close to each other in time, which makes a disciplined hand-hold viable in a lot of situations.

Some one did an analysis recently of a few newer camera’s and the summation was that the effort put in to tweaking ETTR was not longer worth it in newer cameras. The noise so much better controlled and the DR so large that gains were really minimal both visually and statistically. I will try to find the article but it seemed like a reasonable breakdown and again perhaps only true to a point or with certain cameras and lens combinations…

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I found this article to make sense in most cases and I think the most important comment was around composition etc…if you can manage all aspects and get perfect ETTR then I guess great there are some possible gains but if focussing on the ETTR doesn’t allow for other aspects like lighting composition and focus to be given as much attension as they should then perfect ETTR on an out of focus subject won’t be much good…between improvements in sensor quality and the auto bracketing that goes on in HDR modes now on phones and likely newer cameras of which I don’t have a good example …there may at least be diminishing returns to ETTR unless you know your camera so well you can quickly dial in the right amount of extra EV from experience…Exposing to the Right Explained.

How about submitting it to the Play Raw section and getting people’s interpretations?

Some people prefer warmer images, some saturated, some contrasty, some not… a lot of variation. Images should be under a CC license. There’s also a lot of variation based on people’s screens and whether they are using “Night Shift” or “Night Light” :wink:

I have been “doing” photography since the late 70s (well, since the early 60s if you want to count my early days with a Kodak Instamatic), and I sheepishly admit that I had to look up “ETTR”. Here is a pretty good explanation, if anyone else needs it:

Exposing to the Right

It is the opposite of what I have been trying to do for the past ten years or so. I have apparently been trying to ETTL, because the auto exposure settings on my DSLR often result in blown highlights, combined with people explaining that it is easy to bring up underexposure, while it is impossible to truly recover from blown highlights.

So, which method do or should “we” prefer?

If shooting RAW for later processing use ETTR, if working for Reuters use Jpegs and expose for the subject ignoring over exposed and under exposed areas (though with ten stops of dynamic range having detail in undesirable areas can be an issue).

Weddings are an interesting scenario where the photographer comes under a lot of pressure to show the pictures to the bride earlier, and yet what is on the rear of the camera as a Jpeg may be underexposed in a safety margin to retain the bride’s dress detail.

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@Tim ETTR makes sense when we talk about digital photography, because we can generally assume that the photometric response of the sensor is linear until we hit cipping. In such situations, we want to maximise the signal-to-noise ratio by increasing the signal across a more-or-less constant noise floor. We can then adjust the gain digitally in post-production and apply a saturation curve as appropriate to the scene.

In the case of film, the characteristics of the film emulsion are fixed, and so it becomes much more important to set the exposure in-camera so that the key midtone aspects of the scene lie within the latitude of the film. In this case, we still want to ensure adequate exposure to avoid having to “push” the film too much during development, but ETTR itself doesn’t make as much sense.

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Agreed that it doesn’t make sense in all situations, though I have found that reducing noise in the shadows (even if the scene doesn’t have that high of a dynamic range) can still be valuable since I often end up wanting to brighten them at least a little. Not having to try and calculate values for ETTR and “just shoot” the AEB is a nice feature to this approach.

That is a great feature. Does it let you take the successive images at different ISO values, or just different shutter speeds like AEB?

Thanks for the link - I agree that shooting at base ISO when doing ETTR makes sense (aside from noise, dynamic range is greatest at base ISO too). It seems hard to quantify how much new cameras can pull back the shadows with less noise, but from what I’ve read that definitely seems to be something that has improved in recent years.

Actually this one that I submitted recently is an example of this, and some of the variations that others posted did indeed look too dark to me on my screen.

Proper Exposure is very debatable with a simple thought exercise. Imagine a green grass lawn, this would be your mid-tone. If there is a shadow over the lawn but the exposure is locked on the sunlit part, then you are going to get a much darker green in the image but is that exposure correct?

It would depend, if you had a person standing in the shade then you are probably going to want to open up and not expose to the right because the quality of light in the shadow is going to be poor, bluish (as the lawn in shadow is lit from the blue of the sky and not the sun), so the proper exposure is going to put the mid-tone of the sunlit grass higher on a histogram and risk blowing it out because otherwise you are going to be raising the shadows where you would have a lot of noise.

It gets funky, when you have two people on the lawn, one in the shade one in the light, then the correct exposure is probably going to be the original (a reflector/ fill-in flash would then be useful).

Take a black cat on a pile of coal, the final image is going to have a histogram where almost every tone is going to be humped to the left, but relying on a camera reading without exposure compensation is going to give a RAW where the histogram is humped in the middle.

The fundamental thing is that the photographer takes control, he/ she makes an active decision what they want in the final image and then exposes for that effect.

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Actually, I think it’s directly related to the improved usuability of high ISO values: in both cases, how far you can amplify the signal is dependent on the S/N in the shadows (the lights usually take care of themselves).

So if, with the same raw developer, an old camera gives good results at ISO 800, and a new one can go to 6400 with the same perceived quality, you’d have a gain of about 3EV in the shadows (very rough estimation).

However, do not just compare results for in-camera jpegs, or developments done with different (versions of) a raw developer: that technology also evolved… And that probably accounts for part of the perceived gain.

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You could of course use one or more neutral gray cards to get a less subjective anchor in your image. In that way, there is a “proper” exposure for the selected gray card. But of course, as soon as you have different lighting situations within an image, there is no “one proper exposure” possible.

I don’t think that that method is very relevant for most amateur photography, although for professionals in certain areas it will be relevant (exact reproduction comes to mind).

A few weeks ago I opened this issue, requesting that a mode be added to the exposure module that allows you to select an area and specify where you want to place it on the brightness scale.

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You seem to be bringing in artistic judgments, which aren’t necessary.

If the dynamic range of your scene is less than that of your sensor, then you can ETTR. The premise of ETTR is that you’re not going to any clipping.

If you dont have clipping, then you don’t need to assign the luminance value of “mid tone” to the sun-lit grass, you can decide this during post.

If the dynamic range.of your scene exceeds the dynamic ranger of your sensor, and you have no.means to control that contrast, like a fill flash, then ETTR is not as applicable and you must select which values you want to record. In this scenario, you will need artistic judgments, as this will determine what detial you can render in post.

Do you have a grey card or an incident light meter? as both would vary in readings depending on whether they are in the shadow or the light, grey cards also vary depending on how they are tilted, even colour temp is subjective.

My POV is that one should know one’s equipment and make a choice to expose for effect, or in Ansel Adam’s terms, expose to get the best negative possible to produce a print (digital or film), which is the same as shooting a portrait in shadow and exposing to blow the background out or shooting one in sunlit and blocking up the shadows behind the subject. It’s also the same as Mr Adam’s choosing to show as much detail in a landscape as possible. It’s all about the photographer choosing.

I disagree, I’m very technical.

Not quite. If shooting in shadow but exposing for the highlights, in post one would be raising an image of person that would be blue and significantly more noisy than necessary. ETTR would give a poorer end result even though the RAW would have an even spread of tones across the histogram.

It only lets you vary exposure in stops, and while it’s not explicitly said, I believe it does that in the selected exposure mode (P,S,A). I wouldn’t see the utility of varying ISO, as it’s the amount of light on the sensor that primarily influences noise and that’s a function of exposure.

I agree completely. But

  • there are cases where an objective anchor in the image is needed;
  • having an area of known gray value can help in giving a basis for a defined exposure.

How to use that extra information is up to the photographer/editor.

And of course the reading on the gray card will vary depending on where in the scene it is. That’s why it’s used, to get a scene-defined value in the image. Again, how to use that is up to the photographer.

There are several factors in play here:

  • How do I expose the raw file to get optimal information: there you have to avoid clipping the important highlights, and where a middle gray zone ends up is not all that important.
  • How do I then edit that raw file to get an optimal rendition. There, a defined value in your scene gives you a known starting point.

Your exemple of a person in the shadow, in a scene exposed for the highlight is a bit of a red herring, as you are mixing two concepts: white balance and exposure. You can very well expose for the highlights with a whitebalance set to shadow. The more so as changing the camera white balance setting doesn’t change the raw file (it will change the embedded jpeg, but who cares?).

And if you expose for the highlights in such a scene, one assumes those highlights are important, so you need to keep detail there.
And Mr Adams didn’t have quite the same equipment as we have nowadays (which does not invalidate his words, but changes how to act on them).

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