Last updated:- 12th November 2024
Introduction.
Considering image quality, which is more important, the photographer or the camera? Forum experts claim most photographers agree the sensor is more critical. Another myth promoted on forums is a general need for high-resolution sensors and more Dynamic Range (DR). It's sometimes good to remind ourselves why we do photography or select a specific camera or format. This article summarizes my takeaways after visiting the M43 forum at DPReview. These takeaways describe the contrasts between real-life photography and the talking points (narratives) pushed by marketers.
Landscapes with dramatic clouds and deep foreground shadows are known for having a higher dynamic range. The light reflecting from the clouds and deeper shadows increases the ambient DR, which adds to the complexity of photographing and editing these scenes. The Olympus Bracketing and Auto HDR (High Dynamic Range) functions are two ways of capturing and managing High DR scenes.
This article reviews the practical or hands-on aspects of digital photography, exposure, and image editing. You will find more information about the following in this article:
- The Micro Four Thirds (M43) sensor format plus a short history.
- The Technical versus Optical characteristics of the digital camera.
- Why are social media discussions about dynamic range only sales talk?
- More advanced exposure techniques versus the sensor does everything.
- Why did the HDR and ETTR techniques become less popular after 2012?
- The image sensor's role versus the image processor and post-processing.
- What does it mean to paint with light or consider the light conditions?
- How do photographers balance (control) the scene's dynamic range?
- A short video discussing Workspace, Raw conversion, and image editing.
- Features like Stacking, Auto HDR, Bracketing, Composite, and others.
TIP: It's best to study my images on a large display...
All digital cameras have technical limitations, such as too little dynamic range, rolling shutter (sensor readout speed), image noise, and others. Acknowledging these limitations, the Olympus engineering team created innovative features like Auto HDR, stacking, composite, and computational features such as high-resolution mode, ND filters, SCN modes, and a new digital recording format.
The M43 format is a unique digital design. The goal was to optimize the image signal path from the lens to the sensor, the lens flange design, the pixel entry angle, and Shot Noise. The Olympus engineers focused on Sensor Sensitivity or more Efficient sensors. Live MOS sensors benefit from larger photon-sensitive areas and are +25% more efficient than Standard CMOS sensors.
See the short video I created about types of sensors and the new OM-1 sensor.
Why did Olympus use the 4:3 ratio? The 4:3 ratio fills the sensor's image circle more efficiently than the older 3:2 ratio. This enabled Olympus to design high-efficiency Zuiko lenses with 90-degree entry angles (photons) onto the Live MOS sensor. The Olympus engineers created a new format that would continue to benefit from design and future Optical and Quantum Efficiency improvements.
Does the 4:3 ratio improve our Image Quality? Photographers do not determine the efficiency of the reflected light path to the sensor. Considering the 4:3 ratio, the IQ benefits are typically less than 1%. Manufacturers benefit from the M43 format because many such improvements make a big difference. Most FF sales arguments or "fact statements" fall into the less than 1% better IQ category.
What are the benefits of Olympus (Zuiko) M43 lenses? Study this info.
See this interesting article comparing the IQ of 15 cameras.
Complex digital camera components like the image processor, image sensor, IBIS, and computational functions like Auto HDR and the High Ress mode did not replace the need for knowledge, skills, advanced lighting, and camera knowledge. They also didn't replace the need for a tripod, fill-in flash, lens filters, diffusers, reflectors, remote shutter control, or any other photography skill.
IBIS gave us more freedom and sharper images in diverse conditions. That said, IBIS did not replace the need for a tripod in critical situations. The same is true for having more efficient sensors with less image noise at higher ISOs or more advanced camera noise plus AI noise filters. It's always the more creative option to plan or patiently wait and select the best lighting for your photos.
Advanced landscape and street photographers carefully select their locations, equipment, weather, quality of light, and sunrise/sunset times. Extraordinary images require planning and a series of short 3-minute photo sessions in perfect lighting windows. For example, the lighting could be ideal until the next cloud covers the sun. Capturing those special moments and great scenes plus post-processing can take days and hours. It's not a case of large sensors and randomly point-and-shoot photos.
This is one of my favorite photographers. See his last two videos...
Advanced photography means you know your camera, editing, and how to apply lighting. The various "tree" images illustrate this concept of painting with light. I like to select an optimum dynamic range between the highlights, mid-tones, and shadows with the right time of day, clouds (diffused light), and the sun's (incident light) position. The above EM1 III image benefited from the afternoon sun, rich color, and increased mid-tone plus shadows reflected light reaching the RGB filter and sensor.
The above trees illustrate why knowledge and experience are as critical as the camera. For example, older cameras like the Olympus EM5 and Stylus 1s capture good image quality with good light. Studio photography is another genre that illustrates how we manage ambient light. The above trees show the potential of reading a scene and prepping the photo, the camera, plus image editing.
What about the camera's dynamic range? Camera reviewers and forum "experts" push oversimplified theories like "bigger is better". For example, they will say the EM5 II in the above example has less dynamic range than the EM10 IV. Does it mean the EM5 II has too little dynamic range to capture more shadow details or did I use the worst time of day? The Photons to Electrons graph (Figure 1) shows how we control the digital camera's dynamic range with the reflected light exposing the sensor. In addition, Olympus developed several options to tweak the camera's Gamma (tonal) curve.
This means we as photographers determine the sensor's Saturation and SNR. This is huge because the benefits are way more than 1%. Always ask FF forum "experts" (promoters): How much will your FF promises improve my image quality and how do I implement (manage) these benefits?
The images in this article were done with my EM1 III, EM5 II, EM10 IV, and EP-7.
Technical and Optical Characteristics.
Why Technical and Optical characteristics? Modern marketing programs and simplified commercial theories are designed to support sales. The most effective way to learn more about digital cameras is to start with the differences between Optical and Technical characteristics:
- Optical characteristics like FOV, DOF, and lenses are linked to the sensor image circle.
- Technical characteristics like DR, SNR, and Noise are linked to sensor type and design.
The camera's optical characteristics are linked to the sensor's diagonal measurement. The Lens Image Circle has to cover the complete image sensor. This explains why the 25mm M43 lens is the same as a 50mm full-frame lens, why the Field of View (FOV) of M43 lenses is smaller than full-frame (FF) lenses, and why it's possible to design physically smaller M43 lenses than FF lenses.
Diagonal measurements determine lens factors.
Technical information helps photographers because it describes the design and type of sensor, camera features, and image processor. Contrary to social media FF promotions, sensor size doesn't guarantee better image quality. An experienced EM1 III photographer will get similar IQ results in the same light conditions as forum "experts" with FF cameras. For example, technical information helps us to master the technical limitations of all digital cameras. Technical details are valuable when reviewing and analyzing a new digital camera and image sensor. The technical limitations of digital cameras are standard and they benefit most from photographers with knowledge and experience.
Do large sensors deliver more color? The theory behind color is basic. The camera removes the color information from the reflected light with an RGB filter covering the sensor, which means the sensor captures Black-and-White images. The Image Processor uses the RGB filter values, WB measurement, and the sensor's B&W image info to recalculate the final color information in 8, 12, or 16 bits. The quality of light and the camera's Image Processor is responsible for the final Color Rendering.
The practical side of Optical and Technical knowledge. Social media experts rely on the size of the sensor. The value proposition of the "bigger is better" theory is little image noise, more color, higher dynamic range, and image quality. Experienced photographers manage the camera's technical and optical features (camera settings, lens, framing, plus options) to match the scene, time of day, and lighting. The benefits are technical and optical control plus more creative freedom.
Does technical information improve my photography? Technical papers and the following Photons to Electrons graph explain that the sensor's Noise Floor consists of Read Noise (Temporal and Dark) and Shot Noise. Social media experts focus only on Shot Noise because the "size and capture" theory says larger sensors capture more light with "less" noise. Wouldn't the shot noise increase with more light? (Fig. 1) A better way is to control any visible noise (noise floor) with the sensor's SNR and Saturation. The Photons to Electrons graph summarizes several key aspects of an image sensor.
See this link for a recent paper discussing image sensors.
Photons to Electrons Graph. Each photographer should study Figure 1. Did you know that the typical grainy effect is caused by Temporal image noise? The sensor's noise floor (Dark and Temporal noise) is active when we turn the camera on. The sensor only produces an image signal once the reflected light exceeds the sensor's AST (Absolute Sensitivity Threshold). I added the histogram to the above graph to help photographers visualize the visible shadow noise with smaller SNR values.
Why is the push for more pixels a marketing action? Each pixel needs control wiring. More wiring and connection points increase the sensor's Read Noise. That is why we see more shadow noise from cameras with 30MP or higher. The optimum resolution for as many as 90% of photographers is 12 to 24MP. How often do you use the High-Resolution Mode on your Olympus camera?
This article (test) by Chris Hau and his team compares 12MP to 100MP.
The Average Scene Luminance in the exposure formula (Fig. 2) is proportional to Reflected/Incident Light, time of day, and weather conditions (quality of light). That's why Pro photographers work with light. The role of the Aperture and Shutter when Exposing the sensor is also critical. Photographers use these external and camera variables to manage the sensor's Saturation (DR) and SNR.
A short summary of the camera's Exposure Variables are:
- The Aperture and Shutter Speed expose the image sensor
- The ISO setting amplifies (brightens) weaker image signals
- Flashes and Diffusers control the Average Scene Luminance
- The time of day and the sun change the scene's Luminance
- Different materials and colors influence Reflected Light
Do we need all this knowledge? A better understanding of how the digital camera works is enough. It completely changed my photography, technique, and editing style. Knowledge is a benefit in difficult situations such as blue-hour photography, wildlife, and high-speed cases like dogs playing.
The Image Signal Path is the final part of this Technical and Optical summary. The next illustration gives us a basic overview of what happens in the camera. This is a helicopter view of the image signal path inside digital cameras. The illustration was designed to assist digital photographers with enough information and know-how to master the image sensor's Saturation and SNR performance.
This flow diagram is the key to mastering Workspace and the Enhanced Raw Format.
See this video discussing more advanced exposure techniques.
What did we learn from this article?
Final thoughts.
