How to read the DxOMark Image Quality database

Last updated:- 19st April 2024

DxOMark has been in the image quality business since 2003. They empower photographers with good information and knowledge, helping them make informed and autonomous decisions. They translated this goal into a unique Image Quality Database, which many photographers use to learn more about their cameras. The test data also enable photographers to use their cameras more efficiently. 

Did you know DxOMark does not support the "size and capture" theory? It's exciting to discover how they use a theoretical model to test, evaluate, and present their test data on camera sensors.

Please visit DxOMark.com and demonstrate your support by liking my EM1 II conversation with DxO. Add comments and ask DxO for updates on the EM1 III, EM1X, EP-7, EM10 IV, and OM-1.

Note:- The Olympus EP-3, EM5 II, and G11 images were done for this article...

Do all 16MP and 20MP Olympus cameras have Good Image Quality?

                                                                                                                        Source:- DxOMARK

The challenge with finding a new camera is repetitive expert opinions and commercial bias. Accurate information became a rare marketing quality in 2023/2024. For example, many photographers see no or little IQ benefits when they "upgrade" to a new camera or format? It is, therefore, comforting to know that DxOMark uses its own scientists and camera test engineers.

With a small camera portfolio, DxOMark became one of only a few companies using a theoretical test procedure for Camera Sensors and IQ. With almost 400 tested cameras since 2012, they created one of the most reliable test results (databases) for camera sensors, lenses, and image quality.

Olympus EP-7 with 17mm f1.8 lens, ISO200, f7.1, 1/800 - Raw file converted and edited in Workspace.

We are focussing on the DxOMark Image Quality database. While relevant, the DxO database does not include data on computational features, size/weight comparisons, auto-focussing, or the practical aspects of using the camera or lens. For example, I always enjoyed my Olympus EM1 II, but the EM1 MKIII supercharged my passion for Olympus and computational photography.

I tested the impact Pixel Area has on 15 cameras in this article...

Olympus EP-3 with Lumix 20mm f1.7 lens, ISO200, f5, 1/500 - Raw converted and edited in WS. This is the EP3 "OOC" jpeg look.

This article reviews the test results DxOMark published over the past 11 years. These test results can be found in the sensor (image quality) database at DxOMark. I also included a short example of using these test results and how they benefit M43 photographers. Finally, I added an example of preparing any camera for "acceptable image quality" and what that looks like in real life.

See this DxO article discussing the challenges of designing mirrorless camera sensors...

Olympus EM1 II

How should we interpret the above DxO Scorecard? DxO publishes a scorecard on its website for each tested camera. The scorecard includes an Overall Test Score, Color Depth in Portrait mode, Dynamic Range in landscape mode, and Low Light ISO performance in Sport mode. The summary markers (below) apply to the overall score plus the 3 applications DxOMark reviews. 

Also, study the summary notes from DxO in blue:-

Overall Score

• The DxO tests are done at the camera's base ISO and using a logarithmic scale.
• They measure sensor sensitivity, color depth, and the sensor's noise floor.
• The difference in sensor sensitivity is 0.3EV for every 5 points.

Portrait

• The higher the color sensitivity, the more color nuances can be distinguished.
• A 22 Color Depth means the sensor or camera is an excellent performer.
• Anything less than 1 point between 2 cameras is insignificant.

Landscape

• DxO regards a dynamic range of 12EV as sufficient (excellent).
• There is no significant DR variance between the EM1 II and 13.3EV.
• A 0.5EV difference between cameras can be regarded as insignificant.

Sports

• DxO measures the sensor's Saturation and SNR (logarithmic) at the camera's base ISO.
• The Low Light ISO rating is set at an SNR of 30db, a DR of 9EV, and an 18-color depth.
• With a linear progression on M43 sensors, an estimated OM-1 Low-Light ISO is +2000 *.
• Considering the GH5 & GH5 II, how much did the EM1 III and EM1X improve (+1600)?
• A Low Light ISO difference of 25% is the same as 0.3EV and only slightly visible.

* Why did I up my estimated OM-1 low-light ISO rating from 1867 (calc.) to +2000? The BSI sensor is more sensitive than Live MOS sensors, plus several TruePic X efficiency improvements. See this link for a more detailed description of the above DxO test procedures.

Photographed with the 40MP Fuji XT-5. Did you know the XT-5's pixel area is less than the EM1 III?

The DxOMark sensor database has several benefits for photographers. For example, the theoretical principles discussed in my articles reflect the theoretical model DxO uses to test camera sensors. A theoretical model says each sensor has a unique Noise Floor while highlighting the importance of Sensor Sensitivity, Saturation, and SNR as indicators to monitor sensor performance... 

The illustration below explains image sensors, saturation, and SNR (noise).

Figure 1.

What do we learn from the DxOMark database? Image sensors are better in 2023, and no 2 sensors are technically similar. The DxOMark database shows that the practical differences between sensors are tiny, and each image sensor is unique from a design or technical aspect. The DxOMark test results also showcase the improvements sensor manufacturers achieved in the past 20 years. 

Study this link.

How to use DxOMark to Compare two cameras. The following example teaches us how to interpret the DxO test database or how we create a visual reference for Acceptable Image Quality. I used the Olympus EM1 II and Canon R because they represent Pro cameras from 2016 to 2018.

The Canon R and the Olympus EM1 II.

DxOMark uses two "Image Quality" benchmarks for digital cameras. The first is what they define as Good Image Quality, and the second is Acceptable Image Quality. Good image quality means a color depth of 22, a dynamic range of 12EV, and a saturated sensor (+30db SNR) at base ISO. Each of the three variables has to be within the specified range for a camera to have good image quality.

What do we learn from the Sports Low-Light ISO? Many "experts" mistakenly suggest this category determines the camera's ability to use high ISOs. This category only specifies Acceptable Image Quality. That means the ISO (amplification) and specific exposure at the sensor to saturate the sensor with an SNR of 30dB, a Color Depth of 18, and a DR of 9EV. Study Figure 1 and this article.

Acceptable image quality is helpful because it shows us more about the sensor's exposure behavior. Do the following test to get a feel for what acceptable image quality looks like with an EM1 II:-

• Find a similar scene to the above EP-3 photo and take an image in A-Mode at ISO400.
• Increase the ISO to 1250 (1312) and take another photo. Inspect your Raw File in WS.

Olympus EP-3 with Lumix 20mm f1.7 lens - ISO200, f5, 1/800. Raw file converted and edited in Workspace. EP-3 "OOC" jpeg look.

Acceptable IQ does not imply we shouldn't use higher ISOs. This DxOMark rating says that any ISO value above 1312 (EM1 II) will underexpose the sensor, which reduces the color depth, DR, and SNR. We discussed sensor Saturation and SNR in these articles. Those studying my articles should be able to optimize any camera at higher ISOs. For example, we can increase (ETTR) the EM1 II/III exposure by up to 1EV. We can also explain why, plus manage visible image noise (Sony A7R4).

Sony A7R4 with FE 24-70mm f2.8 lens. (ISO3200, f7.1, 1/800) The A7R4 had Acceptable Image Quality and visible shadow noise at ISO3200.

What's the main advantage of using a Canon R? Let's say we like to capture a Grey Heron bird in flight (4th image above). That means upping the ISO by 3EV to ISO1600 for an increased shutter speed of 1/4000. The Canon R is within its sport (low light) range at ISO1600 with more than acceptable image quality. The EM1 II will deliver acceptable image quality with an ETTR of +1/2EV. One could also get the +0.5EV by increasing the aperture and ISO800 (similar DOF). Another parameter not included in the DxOMark scorecard is the AI noise reduction from Workspace. The mistake many make is the practical aspects of applying and using M43 versus full-frame cameras. 

Olympus EM5 II (one of the best) with the 12-35mm f2.8 Lumix Lens. ISO200, f5, 1/500 - Raw file converted in Workspace.

Is the visible noise the same for different cameras? An SNR of 30db does not mean the structure of the noise floor is identical for any two sensors. The visible part of the sensor's noise floor is different for the Olympus EM1 II and the Canon R. The reason is the sensor's noise floor is a function of sensor design and not sensor size. Take a few minutes to study the illustration in Fig 1.

Olympus EP-3 with Lumix 20mm f1.7 Lens - ISO200, f5, 1/640. Raw file converted and edited in WS. This is the EP-3 "OOC" jpeg look.

How does one apply the Overall DxO Rating? One of the most critical IQ variables in sensor design is Sensor Sensitivity. The sensor's sensitivity depends on its Optical and Quantum efficiencies plus its Pixel Area. For example, Live MOS, BSI, and low pixel count sensors are Optically more efficient than higher MP or Standard CMOS sensors. See my articles for more info on sensor sensitivity.

Why is it incorrect to say the ISO adjusts sensor sensitivity? The native sensitivity of the sensor is measured and adjusted at the factory. This means the sensor is calibrated for digital cameras as it leaves the factory. Size and capture advocates like to provoke meaningless discussions about the ISO offsets in the DxOMark database. The ISO standard states that the image brightness should double or half at every full-stop ISO adjustment (amplification). Nothing more or less...

EP-3 with Lumix 20mm f1.7 - ISO200, f5, 1/640. Raw file edited in WS. (>Acceptable IQ, Color Depth 20,8, DR 10.1EV, Low light 536)

Conclusion.

One of the most fascinating DxOMark test results is good Image Quality. This implies a color Depth of 22, a DR of 12EV, and an SNR of +30db (saturated sensor) at ISO200. DxOMark data shows that all the 16MP and 20MP cameras from Olympus have Good Image Quality, and the Olympus 10MP and 12MP cameras have more than acceptable Image Quality. Olympus cameras are some of the most exciting and cost-effective photography solutions for family, nature, and street photography.

The tiny IQ differences between M43 and APC sensors are also fascinating. For example, study the Olympus E-M5 versus the Canon 700D or the EM5 II versus the Canon 760D. Research the different sensor types in digital cameras, ie. BSI versus Live MOS or Standard CMOS. Most APC and Canon cameras have Standard CMOS sensors. The DxOMark database also highlights the theoretical inconsistencies in the "size and capture" theory. Finally, it's difficult to speculate why DxOMark failed to test the Panasonic GH5S, G9, and GH6 or the Olympus EM1X, EM1 III, or OM-1.

I trust you know why one can't say cameras have a Noise Floor, Saturation capacity, and Signal-to-Noise ratio (SNR) and simultaneously promote the idea that large sensors have less noise because they "capture" more light (commercial size and capture theory). This explains the animosity towards DxO and the ongoing critique of any DxOMark test results.

Canon G11 IS (10MP CCD), Raw file in PS, ISO80, f4.5, 1/250. (>Acceptable IQ, Color Depth 20,4, DR 11.1EV)

One of the biggest mistakes the "experts" make about M43 cameras is claiming two or more 16MP and 20MP cameras have the same Image Quality. The IQ characteristics of all cameras change with each sensor and Image Processor variation. For example, the various Live MOS sensors and TruePic VII, VIII, IX, and X combos offer meaningful IQ and performance variances.

What are the 5 additional reports DxOMark could add to its database:-

• Basic sensor info - readout speed, AST, and DR.
• Info about the sensor's noise floor, like size and types.
• Create a test criteria to test & evaluate Image Processors.
• Test & present the main benefits of using different sensor types.
• The safety margin (ETTR gap) manufacturers apply at "100%" exposure.

See this article from DxOMark on sensor size and mobile phones - link.

All the best and God's Bless...

Siegfried

This is how I convert my Enhanced Raw Files?

Last updated:- 22nd January 2023

Many photographers convert and edit their raw files with the same software. PhotoLab and Lightroom are examples of converting and editing raw files with the same applications. While safe for accurate White Balance and evenly exposed raw files, converting your Olympus raw files in Workspace and editing the 16-bit Tiff in Photoshop is often a more rewarding editing strategy.

We are studying an example of converting and editing the same raw file with different applications. You should know I used the same White Balance for the various raw converters in this article. My default Color Space is typically RGB for my raw files and SRGB for the web.

Olympus EP-7 with 12-45mm f4.0 lens - Out of the camera jpeg (ISO200, f5.0, 1/100).

The above scene had more shadow detail in real life. It's easy to assume there was no reflected light from the shadows when viewing the JPEG. No reflected light means no image, no matter how hard we push the ISO. The example below is an edited version of the above JPEG. Did the camera capture or process too few color details, or will the Enhanced Raw File reveal more color information?

This is the OOC Jpeg. I increased the shadow brightness with PS.

The Enhanced Raw Format plus Workspace lets us extract more image information from the captured raw data. The key to success is the Exposure Mix we applied with the camera, the Truepic Processor, and its similarities to the Image Processor in Workspace. The Olympus Enhanced Raw Format is unique and helps us to evaluate and adjust most of our camera raw settings in Workspace.

For example, we can fine-tune the camera's exposure compensation in Workspace. That means we can verify our White Balance (18% Gray) and "Gradation" (Gamma) settings in Workspace. See the ETTR technique in the next paragraph. See this article on how to use the Gradation function.

The Gradation "High" option automatically selects the best ETTR values for your image. Think of the Olympus Gradation function as another variable in your exposure mix. You should always ask, how can I improve my image sensor's output signal, and how do I finalize my neutral gray values in Workspace? How do we reset the camera's Gradation values in Workspace? Simply select the default "Normal" option in Workspace. This will reset your image and the final tonal values to neutral gray.

Why would one use the gradation function with techniques like ETTR? We learned the image sensor does better when it is saturated. It's sometimes better to prioritize the sensor's saturation and SNR values over an accurate Neutral Gray in the camera. Think of low-light or high-contrast scenes.

It's good to prioritize Tonal Data with the camera. This is something we will review in more detail in the future. For example, how many of you worked with the Gamma function in Olympus Viewer 3? Those reading my articles can explain the Gamma function and the benefits of using ETTR. 

Also, study my article explaining the Gradation function and this article by Adobe.

It's also good to always keep a Polarizing Filter (PF) in your camera bag. Use it on your camera with the Gradation "High" option to control or cancel any reflections from water or bright surfaces. For example, why does the Spider Cube have a little chrome ball on the top of the cube?

The images below are illustrations only.

Olympus E-P7 with 12-45mm f4.0 lens - Enhanced raw file converted in Workspace (ISO200, f5.0, 1/100).

The real benefits of the Enhanced Raw Format are Step 2

The converted 16-bit Tiff files are edited in the 2nd step. It's normal for more advanced image editing techniques with more image data. Workspace (image processor) and Sensor Sensitivity (captured details) enable us to extract more image data from our Enhanced Raw Files. We know the Olympus Live MOS sensor is more sensitive than Standard CMOS sensors, and BSI sensors further improve the Optical Efficiency of the sensor. BSI sensors are more sensitive than Live MOS or Standard CMOS sensors. High-sensitivity sensors are known for their ability to capture more shadow detail.

More image data and 16-bit Tiff files enable us to apply more advanced image editing techniques, like editing parts of the image separately. The image below is an example of using different editing techniques for the shadows and the brighter parts of the photo. I upped my shadow brightness in Photoshop. The ability to divide and mask the image improves with new editing software.

It's also good to treat sensor sensitivity and image noise separately. For example, all image sensors come with a noise floor. The sensor's saturation level (exposure) and SNR are responsible for any visible image noise. Olympus gave us several options to control and manage image noise. See this excellent video. Unfortunately, the presenter did not add the Exposure Mix to his list.

Olympus E-P7 with 12-45mm f4.0 lens - Raw file converted with Photoshop 2023 - (ISO200, f5.0, 1/100).

I never use Lightroom because my preferred Adobe application is Photoshop. I like Photoshop for my raw, jpeg, and 16-bit Tiff files. Photoshop 2023 seems better than previous versions, especially with Olympus raw files. The 2023 version of the Adobe Raw Converter also improved a lot. 

Adobe said my perfectly working iMac (2014) is too old for Photoshop 2023. I decided to upgrade to a "new" Intel iMac. See the article here...

Olympus E-P7 with 12-45mm f4.0 lens - Raw file converted in PhotoLab 5 - (See the color cast on the house ).

Olympus E-P7 with 12-45mm f4.0 lens - I converted this raw file in PhotoLab 6.1 and edited the Tiff file in Photoshop.

The ClearView Plus setting is a powerful option for PhotoLab and the main difference between the above 2 images. The default value for Clearview is more aggressive, whereas mine is softer. This is also a "point-and-shoot" image and not a textbook example of optimizing the exposure mix. 

See this article for more on IQ and Exposure Mix.

Fuji X-T4 jpeg file in a similar scene. I upped the brightness in PS.

What do we learn about the Olympus EP-7?

The sensor received two different exposure levels in this example. The sensor was less saturated in the shadows with a lower SNR, less tonal data, and more visible shadow noise. The brighter areas saturated the image sensor, with less noise, more tonal data, and a higher SNR. What happens if I increase my exposure mix (shutter and aperture) with 1EV?

The available detail in the raw file means the sensor's sensitivity is good, and the low level of visible noise tells us the sensor's noise floor is relatively small. For example, I only used the "standard" noise reduction option in Workspace, the Prime setting for PL 5, and only a little noise reduction for PS.

This is the best-ever photography and lens combo from Olympus. Each Olympus enthusiast should own at least one like this!!!

The question is, why did I select casual exposure settings with no ETTR? We do not always need 102% image quality. This is important to those "creative" photographers who prefer specific results from selecting different or "creative" exposure settings (Working with different tonal levels). 

The E-P7 is an excellent street photography camera for those working with color, monochrome, and creative techniques. What are the top 5 reasons why this is the best-ever Olympus combo? How was it possible for a forum reject* like the 17mm f2.8 to reach this status? What do you think?

The original images I used for this article (I needed something for WS).

Conclusion

The images below remind us of the EM1 III's excellent image quality with something like the 17mm f1.2 pro lens. Take a moment and consider the 4 cameras in this article. Each camera offers superior image quality with specific strengths and weaknesses. The decision of which is best for you and your needs is no longer a process of evaluating image quality. The Fuji X-H2 and X-H2S are excellent examples. They use unique image sensors to offer specific strengths and benefits...

The process of converting raw files and separately editing the converted 16-bit Tiff files is the same for "normal" images. I convert my raw files in Workspace and edit them with PS or ON-1. I also started to select the jpeg option more often for my EM1 III, the E-P7, and the Fuji X-T5. I edit those jpegs in one session with ON-1. See this link.

This short article summarizes the main conclusions of my journey on image sensors. I don't wish this on anyone. Study my articles to see the effort it takes to break away from the programming effects of the "size and capture" marketing program. Why is this important? You will only master your camera if you step away from anyone promoting the size and capture theory.

Take care and God's Bless

Siegfried

* Undisclosed or paid forum promoters habitat in the negative and are not paid to be positive. - link

Walking the Dog Instagram Pictures

Fuji X-T4 with 35mm f1.4 lens - ISO3200, f3.6, 1/18, -1EV Exp comp (Provia film simulation & handheld) - Raw file converted in PL-6.

Instagram Images

This version of the image was prepped in Photoshop.

Olympus EM1 III with 17mm f1.2 lens - ISO1000, f1.2, 1/30 handheld - The amazing benefits of M43.

Olympus EM1 III with 17mm f1.2 lens - ISO1250, f1.2, 1/13 handheld - Amazing detail and M43 benefits.

Fuji X-T5 with the 23mm f1.4 lens - ISO3200, f3.6, 1/7th, -1EV comp - Jpeg OOC and handheld.

Photowalk and 2-Step Exposure Technique

Last Update: 9 October 2020

My wife and I were driving past the old town Rapperswil at the far end of Lake Zürich. Returning from our appointment, we decided to stop over at Rapperswil and spend an hour or two in this lovely old town. My wife with her EM10 III and myself with my Pen F with my 12-50mm lens.

I also wanted to test the Gossen light meter. The idea was to try the Gossen with more demanding exposure settings like ETTR for street/city photography. (Walimex is a Gossen)

Olympus EM1 II w 30mm Macro, 2x FL600, mini studio, RC Mode set-up the w Gossen

Regular visitors to my blog will know that I have been on a journey studying exposure, the image sensor, and focusing techniques.

While I was searching for information on my Gossen, one thing led to the next and I came across the Sekonic YouTube presenter, Joe Brady. In his videos, Joe demonstrated the benefits of using external light meters with modern cameras. Joe convinced me to add the Gossen to my exposure toolbox.

In the past, my Gossen was tucked away in my photography "to-do" box. This was until I saw Joe's videos. The video below is the first in a 4-part series.

It is now 3 years since I started researching the image sensor. In that time I studied different articles on DPReview and I participated in various (some heated) forum discussions. I always compared the information I learned with theoretical and technical articles published by schools, image sensor manufacturers, the European Machine and Vision Association, and other enthusiast websites. 

Like in all situations, to get to that one thing that matters most, you need to first remove all the smoke and talking. Without getting too much into the sensor size debate, those who did consider changing from one camera system to another, know its way more than sensor size. Three basic factors to consider are buying/selling costs, the size/weight of equipment, and the available lens range.

Pointing out that one thing, I discovered the key to optimum image quality is to operate the image sensor at its ideal SNR. (Figure 1) It was clear, the digital camera is not an artistic paintbrush. The ideal SNR is specific and it happens in a small operating window only. This moved me to re-adjust my artistic expectation of the digital camera. The artistic part of digital photography can be considered as the pre-recording and the post-processing phases of creating the final digital image. 

The image recording phase is simply a data collecting phase and nothing more. The goal is to select the "right" exposure settings that will push the sensor to its ideal performance. This "ideal" performance happens at the sensor full SNR or full Saturation point. (See Figure 1) At full saturation, the sensor will record maximum tonal data at the lowest noise levels.

Even though I like to write more about all the benefits of recording more tonal data, the challenge is, it will quickly grow into a full separate article. (See this article I wrote)

Figure 1

Traditionally I prefer to use Aperture Priority Mode. That said, our photo walk in Rapperswil took about 2 hours. Based on the conditions I knew it was safe to manually select ISO200. Next, I will select my "starting" aperture. For this kind of city scenes, I used f5,6. From here on I will carefully select my focus points, always check the histogram, up the exposure compensation if needed, and then take the image. This is a quick process that will literally take seconds. As you learn more about the 2-step Exposure Technique discussed in this article, the question is, is there any benefit changing to Manual or Shutter Priority Mode?

Olympus Pen F with 12-50mm f5.0, ISO200, 1/500 - Raw file edited in PS (only basic settings)

The above image was taken using my Gossen exposure readout. See the histogram. The Gossen exposure reading was the equivalent of the camera reading plus 0,3EV. The dynamic range the camera will "see" is influenced by the percentage of clouds in the frame. For example, pointing the camera up a little will increase the percentage clouds in the frame and vice versa. When the camera exposure reading is weighted more towards the clouds, the street level shadows and noise will increase. 

Not that shadows generates more noise, what happens is less exposure (image signal) results in a smaller SNR, a drop in tonal data, and more noise. Interestingly, my Gossen was less impacted by how much clouds were in the "frame" and capable of measuring the overall exposure more accurately. 

This is the same image edited in Luminar 4 - As you can see the camera handled the DR well

The above image is an edited version of the RAW file. While editing the RAW file in Photoshop, I knew the RAW file had maximum tonal data, enabling me to push the RAW file a little harder. 

I increased the exposure by applying the aperture "gain" principle with the image below. As the exposure increased, I monitoring the histogram shifting to the right plus how the image brightness increased at the tree and street level. The final exposure compensation I selected was +1(EV).

When you move the histogram to the right, the darker areas also benefit from recording more tonal data. An increase in tonal data does not only happen in the highlights. If you think about it, this is one of the reasons why it's so interesting to work with HDR. I also used the camera over/underexpose warning system to check for any clipping. The sky had a few warnings (red spots), which was OK. 

I am rarely aiming for no clipping. In this example, the clouds did clip a little in some of the white areas. I was OK with that. I will do the same when I have dark shadows. When having no choice, I found it's better to clip select dark shadows to black and prevent having non-critical dark "details" with noise. This is a simple technique Panasonic has been applying to video recording. Below you see the jpeg, directly from the camera. 

This is what the jpeg looks like when applying an ETTR of +1EV

The image below is the edited RAW version of the above jpeg image. I knew the RAW image had maximum tonal data which was reassuring when editing the RAW file.

For those preferring their jpeg files ready out the camera, read the following. The secret is to treat the RAW and the jpeg files differently. The RAW file can be pushed to record maximum tonal data and the jpeg readjusted to mimic the scene. To get a better jpeg result, you might have to tap down the ETTR to +0,3 or +0,5EV. Keep in mind, using a smaller ETTR will give a smaller SNR, and risking more shadow noise. Tip:- Check out the exposure shift function on Olympus.

The next settings will help you "prepare" a jpeg profile for your camera. Use mid-tones (camera curves) to pull back the ETTR compensation (effect). Set your Picture Mode to i-Enhance (not the Mode Dial, leave that on Aperture Priority). You could also add a "safe" contrast using an S-Curve. (Highlights +1 and shadows -1 or -2) The key is to experiment. One will obviously NOT get the same results in the camera as in Photoshop.

Olympus Pen F with 12-50mm f5.7, ISO200, 1/250 (+1EV) - Raw file edited in PS and Luminar 4

Final thoughts on pushing the image sensor and the 2-Step Exposure Technique

If you want to learn more about the basics of ETTR or what "flooding" the sensor is, see this article. When you study the 2-Step Exposure Technique, the first step setting up your camera exposure is to select the right depth-of-field (DOF) and shutter speed in terms of aperture and movement. The second step is to optimize the exposure you selected in step 1. When you completed step 1, you will see the settings below, displayed on your camera:

• ISO200 (Manual setting - see intro text))
• Shutter speed of 1/400 (Aperture-Mode - shutter speed selected by the camera)
• An aperture of f5,6 (Selected by the photographer in Aperture Mode)
• With this example, the Gossen showed +0,5EV "ETTR" for max SNR
• My histogram confirmed that it is safe to shift the histogram with +0,5EV
• Finally, I use the under/overexposure warning function on the camera

In the second step, you will focus on the actual image signal reaching the image sensor. The aim is to expose the sensor optimally using techniques like ETTR. Which one of the above settings will you adjust if you do not want to impact the DOF and shutter speed you selected in the first step? As you know, I manually set the ISO to 200. We also know that ISO does not control the amount of image signal reaching the sensor. The next 2 options are to increase the shutter speed or the aperture.

Something we haven't discussed much is to 

think of aperture as gain.

When you adjust the aperture as "gain", you specifically targeting exposure and not DOF. When you increase the aperture with 1 stop, you basically doubling the exposure on the sensor. This is seriously exposing (flooding) the sensor. The question is, how will this affect the DOF you selected in step 1. Something not talked about much is the flexibility M43 cameras enjoy in terms of DOF. 

When your "starting" aperture (DOF) has been set for city scenes, it's safe to 

slightly increase the aperture "gain" to expose the sensor more. 

An interesting analogy of the camera DOF is the motorcar steering. The "full-frame" steering is direct while the "M43" steering is indirect. We know this M43 flexibility varies from application to application, think of macro or insect photography. Always experiment and compare your own unique photography style first. 

M43 photographers tend to select higher aperture values than necessary. Instead of selecting f5.6 for a landscape, they will select f7.1 or higher. The difference between f5,6 and f7,1 or higher is the "indirect" steering flexibility I am referring too.

Pen F with 12-50mm, ISO200, f5.1, 1/200 and +0.3EV (ETTR)

The same advantage full-frame photographers enjoy on background blur, they lack on DOF. We know Full-frame owners will strongly disagree on forums, while it's nothing new to see serious full-frame photographers use focus stacking on critical DOF applications like with macro or landscape photography.

When you break free from "background blur", you will learn the M43 aperture is one of Micro Four-Thirds cameras' most exciting strengths. The key to unlocking this benefit is to re-think how you work with aperture when using crop sensor cameras. The depth of field you will have at f4,5 is enough for most landscapes, the key is to select the right focusing point. See this article.

This means it was safe to open the aperture with a half-stop in my first image of Rapperswil. This brightened the image plus added 50% more image signal (exposure) onto the sensor without affecting my original DOF (acceptable sharpness).

Take a moment and think about this, for years full-frame marketers successfully distracted photographers by focussing on equivalence and background blur. In the process, they effectively distracted crop sensor Photographers from exploring this exciting DOF versus "gain" technique.

If you really want to see the full impact of using gain to impact sensor performance, apply this technique on small sensor cameras like the Olympus Stylus 1.

The takeaway is to think of aperture not only as DOF but as both DOF and gain. When you expose to the right (ETTR) use aperture (gain), especially in poor light conditions when you already using slower shutter speeds or higher ISO settings. You need as little as half a stop to "flood" the sensor. A full stop gain will seriously flood the sensor. A better-exposed sensor results in a higher SNR, more tonal data, and less noise. This explains why it's so important to also think in terms of gain.

When you practice this simple 2-step exposure technique, it will quickly become second nature. Once you master this concept of working the M43 aperture setting as gain plus DOF, your photography and especially low light photography will improve.

It is a good idea to start practicing with older 12 or 16MP MFT or compact cameras. The benefits are more visible with older image sensors plus it will help you to master the DOF versus gain principle. 

Will the latest and greatest 20MP cameras also benefit from this technique? Absolutely, the only difference is the visible benefits will be less obvious. On some more recent OMD's, like the EM1 III, the camera auto-exposure appears to automatically measure for maximum SNR.

The possible expiry date

Yes, it is correct, the 2-step exposure technique does have an expiry date. The reason is simple, as more M43 photographers learn how to select the right aperture, the window for flooding the sensor will disappear. That means if you currently use f8 for your landscape images, you have a large window for using this gain benefit technique. If you typically using f4,5 with your landscape images, you have no gain window available. That said you could always decide to create this "gain" window for yourself by selecting f6,3 in step 1 of the 2-Step Exposure Technique. The advantage with crop sensor cameras is they have this unique "build-in" DOF flexibility and this has no expiry date.

I posted a brief summary of the new 2-Step Exposure Technique over at the Mu-43 forum trusting that M43 photographers will appreciate any new information that will help them improve their M43 image quality. I am a little surprised by the aggressive response. You will find it here. It makes you wonder who is really interested in helping other M43 photographers get great results.

Pen F with 12-50mm, ISO200, f5.0, 1/350 and +0.3EV (ETTR)

ETTR summary plus a real example

Last Update: 21 January 2023

Much is said and written about ETTR (Exposing to the Right). Enough to believe most photographers see the value of using ETTR. Unfortunately, this is not the case. The challenge is YouTube talking heads and forum experts continuously promote wild statements, resulting in a powerful technique being lost in a cloud of confusion. See this article for more about modern marketing.

We are looking at an example of using ETTR in this article. If you like to see more information, go to this article. Also, see this article discussing the 2-Step Exposure Technique.

Olympus EM1 II with Leica 25mm f1.4 lens - ISO6400 f7.1 1/13Sec w ETTR - Raw file converted in WorkSpace and edited in Photoshop

Think of ETTR as a process of determining the best possible exposure. We know fast shutter speeds are used for sports photography and large apertures for isolating subjects. Sports photographers prefer good light and/or higher ISOs. We also know an underexposed sensor means more image noise.

The key to top image quality is a Saturated Sensor and

ETTR is one of many exposure techniques.

What is Exposing to the Right (ETTR)?

ETTR is a basic process of adjusting the shutter speed and aperture to ensure more reflected light on the image sensor. The key is the sensor. The ISO setting does not control the reflected light reaching the sensor. We know camera sensors perform best when fully exposed. See this article for an illustration showing the different terminologies like luminance and reflected light.

What is the role of the ISO function?

The ISO function is another variable in the exposure formula used in the camera. It's important to remember the ISO setting does not control the reflected light reaching the image sensor. Use Auto ISO for general use and Manual ISO for critical applications. Use a fixed ISO for challenging applications and the shutter speed and aperture to control the reflected light to the sensor. 

For example, select an appropriate ISO for use with the ambient light in buildings and adjust the shutter speed and aperture to find the correct exposure settings for the sensor. Study this article for more information about the ISO function, shutter speed, and aperture.

The most important technique for improving image quality is to know the ISO. 
Avoid the auto ISO setting and learn how to manually set the ISO.

What are the benefits of ETTR?

When you clear away the talk about photons, pixels, and sensor size, then one fact remains. The average consumer camera is designed to record more tonal data in the highlights. That means the camera captures 2x more tonal data for each +1EV of ETTR. The image signal SNR improves with a more saturated image sensor. Image noise increases with an underexposed sensor.

How does one apply ETTR?

ETTR is not meant for every situation. For example, I often use an Exposure Shift of +0.3EV to increase my average exposure. I prefer Aperture Mode and a fixed ISO of 64 or 100 during the day. I will up my exposure settings with another stop in the late afternoon or blue-hour photography.

Assume you have a critical shot and like to have top image quality. The first step is to manually select the ISO. Use the histogram and increase your exposure with the Aperture and shutter Speed.

Tip:- Keep the ISO fixed

Olympus EM1 II screen

Olympus cameras use an Exposure Headroom of up to 1EV. This is why the histogram is less than optimally exposed in Auto Mode. The exposure meter is linked to the exposure headroom. ETTR helps us to manually bridge this exposure headroom. It is critical to practice with your exposure settings. For example, one can increase the exposure by up to 2EV in a blue sky behind the subject. In other situations, it's only possible to safely increase the exposure with 0.5EV. The camera's exposure meter will show an overexposure with ETTR, and the histogram will simply move to the right.

Study the image below. I upped the exposure with 1EV. There was enough dynamic range headroom available to increase the exposure. This is how much the camera meter underexposed the sensor.

Olympus EM1 II screen

General comments

Photographers are told ETTR is only applicable to the camera's base ISO. This is incorrect because the sensor is designed to capture more tonal data in the highlights, irrespective of the ISO value. Promoters will say the dynamic range decreases at higher ISO values. The solution is to use your histogram, the exposure meter, and other visual features to prevent unwanted clipping.

Tip:- The ISO effectively adjusts image brightness and not exposure.

In terms of exposure, the following is critical:-

• Only the Shutter and Aperture determine the reflected light reaching the sensor
• The ISO function only amplifies the image signal coming from the image sensor

The samples and the info below were taken from the first image in the article:-

Conclusion

Olympus cameras generally underexpose the sensor. This is the main reason for the loss of image details and more shadow noise at higher ISOs. Knowing Olympus cameras, we know it's OK to overexpose the sensor with up to 1EV. The key is to monitor your histogram at higher ISOs and shutter speeds, no matter what ISO you need for that next winning image...

How does ISO invariance impact ETTR? Not much because consumer cameras are designed to capture more image data in the highlights. This will not change shortly.

For more on ISO Invariance, read this article.

Below is a description of how to use ETTR

To optimize your camera exposure, apply this simple method:-

1. Fix the ISO to the value you need (Go to the SCP and select the ISO)
2. Confirm the ISO is fixed in M-Mode. The next step is to set the exposure
3. Select your aperture or shutter speed (A or S mode) and check the exposure meter
4. Follow the histogram with the exposure meter on 0EV (this is 18% gray exposure)
5. The camera "auto" mode will generally select a safe or conservative exposure
6. When you see free space to the right of the histogram, increase the exposure
7. Check the histogram as the histogram moves to the right. (Do not go too far)
8. The exposure meter will show you are overexposing by a 1/3, 2/3, or 1EV
9. It's done when you are satisfied with the histogram and the exposure meter... 
10. You can now safely take your image

Your image will be overexposed. This is easy to correct in the camera or Workspace. The result is an image with less noise and more image data to work with in post-processing.

Sony A7 III with 50mm, f1.8 - ISO25600, f7.1, 1/30sec w ETTR - Raw file edited in PhotoLab 3 using PhotoLab 3 noise reduction

See this helpful video from Ron Trek. Rob has a great YouTube channel with lots of information on Olympus cameras. In this video, Rob discusses the Olympus exposure meter, the histogram, and what features we have with Olympus cameras.