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Last modified: 2011-12-13

HDR ToneMap: Creating a Project

Overview

An HDR ToneMap project requires two or more photos. For better results the photos must share the same aperture and same ISO. Each of the photos should show the same scene taken at different shutter speeds.

 

The easiest way to achieve that is to set your camera in Aperture Priority mode (Av or A mode) and enable the bracketing feature. The three or more photos should cover the entire dynamic range of the photographed scene. In other words:

  • The photo with the shortest shutter speed should not contain overexposed highlights
  • The photo with the longest shutter speed should not contain underexposed shadows

 

A good starting point is to take three photos spaced of 2 EV (Exposure Value). For instance:

  • Photo 1: -2EV, 1/1000s
  • Photo 2:   0EV, 1/250s
  • Photo 3: +2EV, 1/60s

 

Scenes with a very high dynamic range may require more than three photos.

 

For high quality results, it is recommended to reduce the Exposure Value and increase the number of photos. For instance:

  • Photo 1: -2EV, 1/1000s
  • Photo 2: -1EV, 1/500s
  • Photo 3:   0EV, 1/250s
  • Photo 4: +1EV, 1/125s
  • Photo 5: +2EV, 1/60s

 

Creating the project is done in four steps:

  • Step 1: locating the folder containing the photos
  • Step 2: selecting a set of bracketed photos
  • Step 3: adding the set to the Project Image Selection panel
  • Step 4: creating the project

 

 

Step 1, locating the photos

In order to create a new HDR ToneMap project, you have to first display the photos needed for the project in the Browse Workspace.

 

Selecting a folder and displaying the thumbnails:

  • Return in the Browse Workspace
  • Click on the “...” button located in the top Browsing toolbar
  • Using the File Dialog, navigate to the folder containing your photos
  • Click on the Open button

 

The Browse Workspace now displays the photos contained in the folder you just selected.

 

Step 2, selecting the photos

 

 

Selecting photos:

  • Scroll the thumbnail list until you see the set of photos you want to use
  • Click on the first photo in the set
  • Shift-Click on the last photo in the set

Or:

  • Scroll the thumbnail list until you see the set of photos you want to use
  • Control-Click on each photo

 

A green frame is displayed around the selected photos.

 

Step 3, adding the photos to the project selection panel

Add the photos selected at the previous step to the Project Image Selection panel.

Adding photos to the Project Image Selection panel:

  • Select the images as explained in step 2 above
  • Click on the Add button located at the bottom of the Project Image Selection panel

 

 

If the panel already contains photos from a previous project, you have first to clear the Project Image Selection list.

Removing all photos from the Project Image Selection panel:

  • Click the Clear button located at the bottom of the Project Image Selection panel

Removing one photo from the Project Image Selection panel:

  • Click on one of the small thumbnails located in the Project Image Selection list
  • Click on the Remove button located at the bottom of panel

 

You are now ready to create an HDR ToneMap project.

 

Step 4, creating the HDR ToneMap project

At this point, HDRengine can create the HDR ToneMap Project. The HDR ToneMap panel should display: “Ready to create HDR ToneMap Project!”

 

 

HDR ToneMap projects have two options: Auto Align and Ghost Removal.

 

What is Auto Align?

If you are not using a tripod the camera may move when bracketing. The Auto Align feature attempts to align the photos when assembling the images.

 

When to use Auto Align?

Use Auto Align only when taking photos handheld. Never use Auto Align when using a tripod. The additional processing always slightly degrades the resulting image. For high quality results, use a tripod and turn Auto Align off.

 

What is Ghost Removal?

The Ghost Removal feature attempts to detect and remove moving peoples and objects in a set of photos.

 

When to use Ghost Removal?

Use Ghost Removal only when photographing non static scenes such as: crowds, cars, trees in windy condition, waves, etc. Never use Ghost Removal for static scenes such as: architecture, real estate, interior design, etc. The additional processing always slightly degrades the resulting image.

 

How to help the Ghost Removal feature?

Ghost Removal is a very complex technology and may fail. For instance, it is not possible to remove several moving objects when they overlap across several photos. The reason is that none of the photos contains the background. The best way to avoid issues is to increase the number of photos. Instead of taking just one set of bracketed photos, you can take two. Though the exposures remain the same for the two sets, the additional images give HDRengine more data to work with.

 

What is the difference between Ghost Removal Method 1 and Method 2?

The two methods use very different approaches to detect and remove moving objects. In most cases, Method 2 is superior to Method 1 especially with photos containing many moving objects. By default, it is recommended to use Method 2. If Method 2 fails, try Method 1.

 

Enabling Auto Align:

  • Click on the Auto Align checkbox located in the HDR ToneMap panel
  • Click again on the checkbox to turn it off

 

 

Enabling Ghost Removal:

  • Click on the Ghost Removal menu located in the HDR ToneMap panel
  • Select Method 1 or Method 2
  • Select No Ghost Removal to turn it off

 

 

After choosing the HDR ToneMap options, you are ready to create the project.

 

Creating the HDR ToneMap project:

  • Click the Create HDR ToneMap Project button located at the bottom of the HDR ToneMap panel

 

HDRengine automatically switches to the Edit Workspace and starts loading the photos.

 

What to do when the HDR ToneMap panel displays an error message?

When your photos do not contain Exif data or have missing Exif data, the HDR ToneMap Panel will display an information message such as: “Shutter speed values are required to build an HDR ToneMap Project”.

 

If this happens you can enter missing data by hand. The Project Image Selection panel works like a small spreadsheet. You can click in any cells to enter a missing value.

 

Manually setting missing data:

  • Click in the cell with the missing value in the Project Image Selection panel
  • Type the missing Shutter Speed, F-Number or ISO value
  • Press the Tab key to validate
  • Repeat until all missing values are entered