Gavin Phillips shows how to use HDR imaging to create superb images with fine detail, perfect lighting and accurate colours.
What is High Dynamic Range (HDR) Imaging?
HDR is produced when you take three to five or seven photos at different exposure settings, and then merge them into a single image using speciality software. What you get are beautiful photos with incredible detail, controlled lighting and accurate colour. You cannot reproduce an HDR image manipulating a single JPEG or raw image in Photoshop.
Below is an example of a set of seven images taken at 1-stop exposure increments, then merged and tone mapped.
The Benefits of HDR
The human eye sees an outdoor or indoor scene quite differently from what can be captured with even top grade professional digital cameras and lenses. Not surprisingly, our eyes are far more complex.
Our eyes adjust for harsher light and render colours and detail more accurately than any single raw file can capture.
With HDR you can produce wonderfully crisp images that have excellent detail and control of lighting. You do not need to worry about harsh sunlight or very contrasty scenes.
Below is an example of my regularly exposed single shot compared to my seven-shot HDR version. When printed, the HDR version has far more detail and an overall richer look to the image.
When to shoot HDR?
- Architectural and Commercial
- Interior shots
- Select wedding shots (church interior, vows)
- Some wildlife (animals standing still)
- Night architectural (need higher ISO 1600+)
- Landscapes
HDR in a Nutshell
- Take 3,5 or 7 shots at different exposures
- Merge bracketed sets into 32-bit images
- Tone-map in HDR specific software
- Finish in Photoshop
HDR Camera Set-up
Always shoot raw files. They are better for HDR than JPEGs because they contain more image data. I have compared sets of JPEG and raw files of the same scene and processed them in Photomatix and Artizen. The results are superior with the raw images.
Auto Exposure Bracketing Mode
Put your camera into the auto exposure bracketing mode. This allows you to run off a sequence of shots at different exposures by simply holding down the ‘shoot’ button.
It will depend on your camera as to how many you shoot in a sequence. Most DSLR cameras offer you up to 1-stop increments in bracketing mode. You would only ever go to a maximum of 2-stop increments. I shoot sets of five or seven at 1-stop increments.
Some recent advanced compact cameras offer raw shooting and Auto Exposure Bracketing. Two that I know of are:
- Panasonic Lumix G3, which offers up to seven shots at a max of 1-stop exposures. This is perfect for HDR.
- Olympus E-PL3, which offers RAW and up to 2-stops in AEB.
Both cameras are easy to carry around and offer a good introduction to digital HDR.
HDR Specific Software
All these software programs are Mac/Windows compatible and offer free trial downloads:
Photomatix Pro offers many features and an intuitive, easy-to-use interface. Its strength is outdoor daytime HDR, where it can really open up shadows and produces very pleasing colours that are easily controlled with the sliders.
The batch processing feature is a huge time-saver. Merging one set of three, five or seven images into a 32-bit image can take from 10 seconds to over a minute, depending on your computer speed and how many images are in the set. If you have more than a few sets of HDR, (at Yosemite I had hundreds of sets) this consumes a large amount of time.
Photomatix’s batching feature allows you to merge dozens/hundreds of sets of HDR images into 32-bit images automatically while you do something else. You then open the 32-bit image instantly in your software of choice and apply the tone-mapping, which is the only part that interests you.
Be aware that with interior shots, Photomatix often introduces a blue cast into sunlight coming in through windows.
Artizen - I use Artizen for most of my interior HDR shots. Most of the time it gives me better results for what I’m looking for with interior shots.
Dynamic Photo HDR - I use DPHDR for some of my night HDR, and some daytime HDR as well. It depends how the image looks. It often creates more natural looking skies, and it’s great if you want to go in a different creative direction. You can get a great variety of different colour effects. Sometimes I see odd artefacts introduced into images; such as burnt-out skies or excessive noise, so I don’t recommend this program as your only HDR specific software. However, it’s a useful creative alternative.
HDR Efex Pro
Like all Nik software, HDR Efex Pro’s user interface is intuitive and easy to understand. I liked the variety of one-click presets and it is easy to keep your HDR looking natural. I still prefer the colour in Photomatix for outdoor HDR, though.
Nik’s patented ‘U Point Technology’ allows you to fine-tune very specific areas in your image without affecting the rest of it.
Photoshop HDR
Basic HDR tone-mapping sliders and presets were introduced in Photoshop CS5 and are also provided in CS6 with expanded functions like HDR Toning. I have worked with CS5 on some sets of HDR and compared it to the tone-mapping I get in the other software. The results are far better in Photomatix, etc.
However, I spend most of my time in Photoshop finessing the image and creating custom imagery.
Single-shot ‘Pseudo HDR’
All HDR software reviewed here gives you an option to create a ‘pseudo HDR’ out of a single raw or JPEG image, although raw files produce the best results. The advantages are that you do not have to take multiple shots and there will be no ‘ghosting’ to remove of people moving in the image.
Pseudo HDRs do not have the same wide dynamic range produced with multiple exposures, they tend to be noisy, and you don’t get the same detail. However when you have rapidly-moving people, animals or vehicles, pseudo HDRs often look far more interesting than just working the image in Photoshop. And they are very quick to process.
HDR and People
You can photograph people selectively with HDR – people posed, or a bride and groom standing still at the altar.
Even if they are standing ‘still’ there is likely to be some slight movement between the frames. This is referred to as ‘ghosting.’ The colour of the people’s faces will be incorrect as well.
To correct this I use one of the bracketed set of regular raw images and Photoshop to selectively mask-in the people into the HDR image. It only takes five minutes. I only take a few HDR images with people in them to capture the occasion in a way I could never achieve otherwise.
My HDR Workflow
First I download all my HDR sets into a folder. I sort the winning sets in Photoshop/Bridge or Lightroom and move them to a ‘Winners’ folder. Different sets must be kept together. Don’t mix a set of three with a set of five or seven; it will completely mess up the batch processing.
Batch rename the winning sets in Photoshop or Lightroom with a number sequence. If I have 20 sets of five bracketed images, it will be numbered 1 through 100.
I then use Photomatix to batch my 20 sets of five into 20 single, 32-bit images. While Photomatix is doing this, I’m in Photoshop or doing something else.
When Photomatix finishes its batching, I go in and open the 32-bit images in Photomatix for tone-mapping. The tone-mapping is very fast. Once I set-up the sliders for the first image, I usually stay pretty close to those settings for the other images. I then finish the image in Photoshop.
Avoiding HDR Issues
Halos can be an issue with HDR images. Halos are usually found where the sky meets buildings or trees in an image. They appear as a line (or band) of lighter sky that doesn’t look natural and is very distracting.
Halos usually result from using extreme settings in your tone mapping, although sometimes you may still see halos, even with conservative settings. In that case you may have to swap out the sky in your HDR image with the original sky in one of the bracketed images in Photoshop.
Over-saturation is easily controlled in all the programs I reviewed here. Once you have the settings the way you like them, you can save them as one of your custom presets.
You have complete control over your image. It is easy to stay within a regular colour range, but still gain a significant advantage by using HDR. You have to watch you do not overdo it, particularly with skies.
Finishing in Photoshop
Although the HDR specific software is great for the merging and tone-mapping stage of your HDR sets, there is no substitute for the final finessing of your image in Photoshop.
I usually use a custom Curves adjustment. You can use the brush tool on the Curves mask to adjust how much of the curve is used in your image and where it is used.
Another excellent, but often overlooked, adjustment is the Shadow/Highlight tool. There may be areas of the image that require careful cloning out. Don’t forget that sometimes you can use the Spot Healing Brush to blend away something small in your image instead of always using the clone tool. Photoshop’s new Content Aware controls are very handy for fast clean-up as well.
The last thing I do is selective sharpening. I use high pass sharpening for all my images that do not have people in the image. You find this under Filter > Other > High Pass. When people are in the image I use unsharp mask or smart sharpening.
Creative Freedom
HDR gets quite a lot of criticism because many of the images are over-worked. However, any image can be overworked in Photoshop or any software.
Some photographers have become so worried about being criticised for using HDR, their HDR images look exactly the same as a single image worked in Photoshop. HDR is different; it has a vibrancy and detail that is great for certain situations.
For some images I go further and use a full range of Photoshop adjustment layers, filters, masking and plug-ins to go in many different directions. We have so many creative tools to work with today; I’m not going to limit myself to staying within a regular photograph all the time.
As the late famous photographer Fred Picker stated, ‘Photographers owe nothing to reality’. I offer my clients both types of images.
Gavin Phillips offers HDR webinars, training movies, custom Photoshop ‘actions’ and Lightroom Presets.
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