Last update:- 20th May 2024
Introduction.
I am busy updating this article. (16 Nov 24)
We are discussing image quality, stacking, and computational photography. Image quality is the sum of the sensor, lens, image processor, and knowledge. Modern Image Processors mean better control and computational features. It's possible to optimize the sensor's Saturation and SNR and Olympus created an excellent range of Standard, Premium, and Pro Zuiko lenses. For example, cameras select an average exposure, and knowledge enables us to use optimum exposures. For example, stacking, composite, bracketing, and computational options mean higher image quality and more creative control, while some say it's all about sensors and expensive cameras...
We are reviewing the Olympus Auto HDR (High Dynamic Range) and Bracketing functions and how they give us more control over our image quality. Auto HDR converts 3 bracketed exposures into one HDR (JPEG) image. Auto HDR and Exposure bracketing give us more dynamic range and tonal data in the shadows and midrange areas of the image. These different Auto HDR and Bracketing options are available with most Olympus EM10, EM5, PEN, EM1, OM5, and OM1 cameras.
Olympus EM5 II with 12-50mm f3.5-6.3 EZ lens - ISO1600, f6.3, 1/80 - 40MP high-Res image edited in Photoshop.
Olympus designed an interesting range of advanced camera features to enable hobby photographers. One can categorize these unique features into four groups:
- Long Exposure times
- Composite Techniques
- Stacking Techniques
- Powerful Tonal Adjustments
- Creative Color adjustments
- Computational photography
- Workspace Raw conversion
The following applications or techniques are linked to these features:
- Traditional bracketing (exposure, focus, white balance, ISO, and ART)
- Computational functions like focus-stacking and high-resolution images
- Editing software like Photoshop has similar options like HDR functions
- Various camera and image editing techniques for more creative results
- Olympus computational functions, Live Time, Live Comp, and ND filters
One way of improving image details is the Photoshop Merge to HDR Pro function. It combines 2 or more bracketed exposures into one high-detail 32-bit image. This method works well for product and landscape photography. The benefits are similar to HDR or the Olympus Hi-Res mode.
The Photoshop Merge to HDR Pro function is also used for traditional HDR images. Follow the image descriptions for examples of stacking 3 or more bracketed images into one HDR photo.
The High-Detail 32-bit function in Photoshop
I selected 3 bracketed exposures from my photo collection to test the 32-bit HDR Pro function. I used Adobe Bridge to open the 3 images in HDR Pro. The high-detail 32-bit Pro option is one of several HDR possibilities. It's now possible to create natural-looking HDR photos. The surreal HDR look is something of the past with the High Detail 32-bit HDR Pro function.
I used 3 bracketed images from my Canon 350D and processed them with the Photoshop High Detail 32-bit HDR Pro function.
Study these 3 Canon 350D histograms. Nobody talked about sensor performance or optimizing the image sensor when I took these 3 bracketed images in 2004. I knew nothing about sensor saturation or SNR. I simply followed forum and magazine advice when taking the 3 exposures.
The histograms show the default exposure was good. The 350D did a great job selecting the best exposure for the initial image. It shifted the shadow and midrange tonal data to the right and protected the highlights. It helps to use your camera frequently and create opportunities and projects to practice these and other Olympus computational features.
Three Bracketed Exposures
Under Exposed Default Exposure Over Exposed
High Dynamic Range (HDR) images
What is the best default exposure for High-Detail and HDR sequences? The principle of merging stacked images into one photo allows the HDR software to select the best tonal data from each image and combine them into one HDR photo. One typically uses +/-1EV steps to create HDR photos. The initial or default exposure should maximize the tonal data for every bracketed exposure.
Another interesting method is Exposure Blending. See this function in Photoshop. It puts 3 bracketed images into separate layers with a mask highlighting the best data for each layer. This lets us see which parts of the bracketed images should go to the final HDR photo. The photographer can tweak these separate masks to focus on specific data areas, noise, and shadow details.
Experiment and practice with your camera's exposure settings and histogram until you find the best exposure technique to complement your photography style. For example, the presenter in the above video used 2 bracketed images to explain the Photoshop "Merge to HDR Pro" function.
Olympus EM5 II with 12-50mm f3.5-6.3 EZ lens - ISO1600, f4, 1/80, -0.3EV - Enhanced Raw file converted in Workspace and edited in PS.
What about the HDR1 and HDR2 functions in Olympus cameras?
The Olympus HDR function is one of the most underrated Olympus features. It is available for most Olympus cameras and can be configured in Shooting Menu 2. The secret is to use the Olympus HDR function in Manual Exposure mode. It's also possible to use Auto or Semi-Auto (A or S) mode...
Olympus EM5 II with 12-45mm f4 Pro lens - ISO200, f4, 1/80 - this is a handheld HDR1 image - the OOC jpeg was prepped in WS and PS.
Use the camera's HDR1 or HDR2 function and set the default exposure for optimum image data. The histogram lets us determine each capture's tonal data range. The camera will automatically select ISO200. That means you need a tripod in low light. The base or starting exposure determines whether your focus is shadow, midrange, or highlight data. For example, use ETTR for the initial (default) exposure to increase your shadow data or reduce the exposure to protect the highlights.
Olympus placed HDR1 and HDR2 in the AP menu of newer cameras like the E-P7. Turn the mode dial to AP, select HDR, and press the down arrow. It is not possible to configure HDR1 or HDR2.
Olympus EM5 II with 12-50mm f3.5-6.3 EZ lens - ISO1600, f8.0, 1/250, -0.7EC - 40MP high-Res image edited in WS & Photoshop.
Conclusion
I discussed different ways to record an image. We understand the basic principles of sensor saturation and SNR and reviewed examples of various computational and exposure techniques. Knowledge is crucial because it lets us do more with the camera and image-editing software. A good example is WS and the Enhanced Raw Format. Is Workspace always better than Lightroom or PhotoLab?
Why does the camera's HDR function need bracketing? Because the shutter and aperture project a uniform exposure (image) onto the sensor. Study my previous articles for more information...
Olympus E-M5 II with 12-45mm f4 Pro lens - 40MP high res image.
Why should one ignore those who criticize the High-resolution function? Experienced photographers plan for movements caused by people or wind when using stacked images to create photos. Typical examples are focus bracketing, exposure bracketing (HDR), and high-resolution imaging. For example, full-frame cameras have a smaller DOF than M43 cameras. You will, therefore, find that many full-frame and medium-format photographers use focus bracketing for landscape photography...
Olympus EM5 II with 12-45mm f4 Pro lens - 3 bracketed exposures processed in "Merge to HDR Pro" and edited in PS.
Which exposure technique is best? Knowledge is an enabler and necessary. It's good to know more about sensors and how we optimize their performance because digital cameras can do more and are more complex than analog cameras. That's also why I spent so much time on the image sensor and managing its saturation and SNR. This article illustrated different computational and image results. Each scene is unique and benefits from an experienced photographer showcasing its beauty. The type of scene and final image determine which exposure technique is better...
The Olympus E-M5 II is a surprisingly capable camera in 2024 and can be bought "like new" for less than $250. It has almost all the computational and video features of the E-M1 II. Used Olympus cameras like the E-M10 II, E-M5 II, E-M1 I/II/III, and the E-PL8/9 are selling at bargain prices...
Best
Siegfried
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